Biology today september 2016

They are both protected by hard bony coverings-the brain by coverings-the cranium and coverings-the spinal cord by coverings-the vertebral column and by a continuous, tough, layered memb

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CENTRAL AND PERIPHERAL NERVOUS SYSTEM

CENTRAL NERVOUS SYSTEM

The central nervous system (CNS) is the processing centre

of the nervous system It receives and sends information

to peripheral nervous system The brain and spinal cord

are continuous structures, which together form the

CNS They are both protected by hard bony

coverings-the brain by coverings-the cranium and coverings-the spinal cord by coverings-the

vertebral column and by a continuous, tough, layered

membrane called the meninges Both the brain and

spinal cord are bathed in cerebrospinal fluid (CSF),

which is continuously circulated through the

cerebral ventricles, the cavity of the spinal cord

and the sub-arachnoid space It serves as a pad to

cushion the CNS from shocks and mechanical injuries

The CSF also carries oxygen and nutrients from the

blood to the neurons and neuroglia of the CNS

Together, the brain and spinal cord act as the central

control system of the body, receiving and interpreting

sensory information from the rest of the body and sending back

signals to glands and muscles for appropriate responses

Cranium

Ventricles

Cerebrospinal fluid (CSF)

Meninges

Spinal cord Spinal cord cavity

HUMAN BRAIN

The human brain is the command centre for the human nervous system It receives input from the sensory organs and sends output

to the effectors It processes and interprets sensory information sent from the spinal cord The brain is covered by three protective

layers of connective tissue called meninges.

Space between arachnoid

membrane and pia mater and is

Dura mater

Outermost, tough, fibrous membrane adhering closely to the inside of the skull

Parietal lobe of cerebral hemisphere

Occipital lobe of cerebral hemisphere Anterior choroid plexus

Thalamus (encloses third ventricle) Pineal body (part of epithalamus)

Cerebral peduncle of midbrain

Cerebellum Fourth ventricle Arbor vitae Posterior choroid plexus

Cerebral aqueduct Corpora quadrigemina Corpus callosum

Temporal lobe of cerebral

hemisphere Mammillary body

Pons

Mid brain

Medulla oblongata Spinal cord

Anterior commissure

Pituitary gland Infundibulum

Optic chiasma

Hypothalamus

Fig.: Median Section of Human Brain

Forebrain

Olfactory Lobes- Paired club shaped structure, forming anterior part of brain, concerned with sense of smell Each lobe consists

of two parts - anterior olfactory bulb and posterior olfactory tract.

Cerebrum

Largest and most complex part of human brain, consists of left and right hemispheres, connected by corpus callosum (large band of myelinated fibres) Cerebral cortex forms outermost portion of cerebrum and makes up the grey matter The surface of cortex is highly folded, forming gyri (upward folds) alternating with sulci (downward grooves).

Cerebral cortex forms white matter of the brain It contains million of medullated nerve fibres, connecting neurons of cerebral cortex with those located elsewhere in the brain Large concentration of medullated nerve fibres gives an opaque white appearance.

Lies in the left temporal lobe

Forms anterior choroid plexus

s

Short pineal stalk, have pineal body,

s

secretes hormone melatonin.

Lies superior to mid-brain

to it by stalk called infundibulum.

Maintains homeostasis, provides anatomical connections

of mid brain are called corpora quadrigemina.

One pair is called

s superior colliculi (concerned with sense of sight)

and other pair is inferior colliculi (concerned with hearing)

The superior and inferior colliculi of each side are termed

Cerebellum has two lateral cerebellar hemispheres and central worm shaped part, vermis.

It contains branching tree like arrangement of grey and white matter called arbor vitae (tree of life).

Functions: Controls posture, balance and mainly involuntary activities, receives information from muscles, joints, skin, eyes.

Second largest part of the human brain, consists of 3 layers, outer layer of cells, cerebellar cortex and deeper cell clusters

Middle layer contains characteristically large flask shaped Purkinje cells.

Pons Varolii

Functions: It relays impulses between the medulla oblongata and superior part of brain, between hemispheres of cerebellum and

between cerebrum and cerebellum.

Pneumotaxic centre present in pons varolii limits inspiration.

It is situated in front of cerebellum below the mid brain and above the medulla oblongata.

Medulla Oblongata

It has thin, non-vascular folded structure on its lower side called posterior choroid plexus

Functions: Regulatory centres for heart rate, blood pressure, breathing, sneezing, salivation, coughing etc.

Pyramid shaped, extends from pons varolii above and is continuous with spinal cord below

The mid brain, pons varolii and medulla oblongata are collectively called brain stem, connecting forebrain with spinal cord

Ventricles of the Brain: Within the central nervous system is a system of hollow cavities called ventricles The network of

linked cavities in the brain (cerebral ventricles) is continuous with the central canal of the spinal cord The ventricles are filled

with cerebrospinal fluid which is produced by specialised epithelium located within the ventricles called the choroid plexus.

Fig.: Ventricles of Human Brain

Interventricular foramen (Foramen of Monro)

Connects lateral ventricle to the third ventricle

Inferior tip of lateral ventricle

Cerebral aqueduct or Aqueduct of Sylvius or iter

Present in the midbrain portion of brainstem, connects

third ventricle to fourth ventricle in pons and medulla.

Third ventricle

Consists of narrow channel between the

hemispheres through the area of thalamus.

Fourth ventricle

Continuous with the central canal of the spinal

cord, openings in fourth ventricle, allows CSF to

move upward to the sub-arachnoid space that

surrounds the brain and spinal cord.

Cerebellum

Central canal

CEREBROSPINAL FLUID (CSF)

The cerebrospinal fluid is secreted by anterior choroid plexus and posterior choroid plexus and is found inside the ventricles

of the brain, the central canal of the spinal cord and in the sub-arachnoid space around the brain and spinal cord

Excretion- CSF carries harmful

metabolic wastes, drugs, and other substances from brain to the blood.

Endocrine medium for the brain - CSF carries

hormones to different parts of the brain.

HUMAN SPINAL CORD

Location-The spinal cord is a cylindrical shaped bundle of nerve fibres

that is connected to the brain It runs down mid-dorsally, in the centre of

the protective spinal column extending from the neck to the lower back It

lies in the neural canal of veretebral column Spinal cord nerves transmit

information from body organs and external stimuli to the brain and send

information from the brain to other areas of the body

Covering Meninges - The spinal cord is surrounded by three protective

membranes; innermost piamater, middle arachnoid membrane and

outer, tough duramater The sub-arachnoid space is filled with cerebrospinal

fluid and the additional epidural space, above duramater contains fatty

and connective tissues and veins

Posterior (dorsal) root spinal nerve.

Axon of sensory neuron

Posterior grey horn

Axons of dorsal nerve root forms synapse with other neurons, called interneurons.

Axon of motor neuron

Posterior median sulcus* White column

White matter having bundles of myelinated nerve fibres.

Lateral grey horn

Lies between anterior and posterior horn.

Nerve impulses for sensations Nerve impulses to effector tissues (muscles and glands)

Cell body of sensory neuron

*Posterior median sulcus and anterior median fissure separate spinal cord into left and right symmetrical halves.

Fig : T.S of Human Spinal Cord

Posterior (dorsal) root

ganglion

Consists of cell bodies of

dorsal nerve root, having

sensory axons.

Central canal

Hollow, contains CSF.

Anterior grey horn

Contains cell bodies

of motor neurons.

Cell body of motor neuron

Anterior median fissure*

Spinal nerve

A spinal nerve arises from

each side of cord, in each

segment of spinal cord.

Grey matter

Inner butterfly (H)

shaped area of spinal

cord, lacks myelin.

Anterior (ventral)

root of spinal nerve

Aggregations of motor

axons from cell bodies

present in anterior (grey)

horn, form ventral

nerve root

Functions- Spinal cord performs two main functions:

(i) The stimuli are passed from and to the brain through the spinal cord

(ii) It is the centre of spinal reflex action

PERIPHERAL NERVOUS SYSTEM

Peripheral nervous system (PNS) is the nervous system outside the brain and spinal cord It consists of cranial nerves (nerves

originating from brain) and spinal nerves (nerves originating from spinal cord)

Skull bone Skull bone

Foramen magnum C1 vertebra

C7 vertebra T1 vertebra

Dura mater Pia mater Arachnoid mater

C1 nerve C1 vertebra

C7 vertebra T1 vertebra T1 nerve

Fig : Coverings of Human Spinal Cord

T1 C8

C1

Cranial Nerves

There are 12 pairs of cranial nerves They are so named because they pass through various openings in the cranial bones

Table: Cranial nerves

1 Olfactory Olfactory epithelium in

nasal cavity

3 Oculomotor Floor of midbrain Eye, 4 muscles of eyeball Motor Movements of eye-ball, iris, lens,

eyelid and constriction of pupil

skin of forehead, eyelids etc

Cheeks, upper gums, upper teeth –

and lower eyelidsTeeth and gums of lower jaw, pinna –

of the ear, lower lip and tongue

Mixed

SensorySensoryMixed

Skin sensationsSensationsSensations, tongue movements, mastication

6 Abducens Pons varolii External rectus muscle of eyeball Motor Rotation of eyeball

Mixed Taste, facial expression, chewing,

Organ of Corti in cochlea, semicircular canals

Sensory Hearing and equilibrium

9 Glosso-pharyngeal Lateral side of medulla Posterior 1/3rd of tongue, soft palate

and muscles of pharynx

Mixed Taste and touch, movements

(swallowing) of pharynx, salivation

Also called wandering nerve as

it has maximum branches

Mixed Vocal cords (sound production),

lungs, respiratory reflexes, peristaltic intestine movements, speech, swallowing, secretion

of gastric glands, inhibition of heart beat

Motor Movement of muscles of

pharynx, larynx, neck, shoulder

12 Hypoglossal Ventral side of medulla

oblongata

Muscles of tongue, hyoid apparatus Motor Movement of tongue

motor: all eye

muscles except those

supplied by IV and VI

Trigeminal (V)

sensory: face,

sinuses, teeth, etc.

Facial (VII) motor:

muscles of the face

Hypoglossal (XII) motor: muscles of

the tongue

Fig.: Cranial Nerves

Accessory (XI) motor:

muscles of pharynx, larynx, neck.

Sensory: heart, lungs,

bronchi, trachea, larynx, pharynx, gastrointestinal tract, external ear

Intermediate motor:

submaxillary and sublingual gland

Vestibulocochlear (VIII) sensory:

inner ear

sensory: anterior

part of tongue and soft palate intermediate

nerve

vestibular cochlear

Glossopharyngeal (IX) motor: pharyngeal

musculature

motor: muscles

of mastication

Olfactory (I) sensory: nose

I I

Structure - The spinal nerves are formed by union of dorsal and ventral roots shortly after they leave spinal cord Each spinal

nerve has afferent (sensory) and efferent (motor) fibres, in general, efferent comes from ventral root and afferent go into dorsal

root Thus, all spinal nerves are mixed nerves because they carry both sensory and motor impulses.

After leaving vertebral column, each spinal nerve divides into:

–

Posterior branch- innervates muscles and skin of the posterior portion of the body.

Anterior branch- innervates limbs and the lateral and anterior portions of the body.

The main spinal

Connects pelvic region

Autonomic Nervous System (ANS)

This system controls and coordinates involuntary activities of various organs, e.g., secretion of digestive fluid.

ANS is divisible into two parts: Sympathetic and parasympathetic neural system

Table: Differences between sympathetic and parasympathetic neural system

Sympathetic Neural System Parasympathetic Neural System

Anatomical Differences

(i) It has paired chains of ganglia and other visceral ganglia Chains of ganglia are absent It has ganglia very close to

the organ supplied

(ii) Its preganglionic fibres originate from the spinal cord Its preganglionic fibres originate from the brain and spinal

cord Those preganglionic fibres which come from the brain run along with the III, VII, IX and X cranial nerves while those coming from spinal cord pass through 2,3 and 4 sacral spinal nerves

(iii) Its preganglionic fibres are shorter than the postganglionic

fibres

Its preganglionic fibres are much longer than the postganglionic fibres

(iv) Each preganglionic fibre forms synapses with many

postganglionic fibres, so many organs are affected

Each preganglionic fibre synapses with only a few postganglionic fibres, thus, only one organ may be affected

Physiological Differences

(v) Its postganglionic fibres are adrenergic i.e., release the

neurotransmitter noradrenaline (norepinephrine)

Its postganglionic fibres are cholinergic i.e., release the

neurotransmitter acetylcholine

(vi) It stimulates the medulla of the adrenal glands to release

epinephrine and norepinephrine

None

Table: Differences between adrenergic and cholinergic nerve fibres

(i) These nerve fibres release neurotransmitters

adrenaline and noradrenaline at their terminations

These nerve fibres release neurotransmitter acetylcholine at their terminations

(ii) These are generally preganglionic sympathetic

fibres

These are generally all sympathetic and parasympathetic preganglionic nerve fibres and all parasympathetic post ganglionic nerve fibres.The functions of sympathetic and parasympathetic neural systems are antagonistic to each other

Dilates pupil

Dilates bronchi Accelerates heart beat

Inhibits saliva secretion

Stimulates epinephrine and norepinephrine release

Inhibits stomach, pancreas, and intestine secretion

Promotes ejaculation and vaginal contractions

Relaxes bladder Stimulates glucose release

Parasympathetic division

Constricts pupil Stimulates saliva secretion

Stimulates stomach, pancreas, and intestine

secretion

Promotes erection of

genitals

Constricts bronchi

Constricts bladder

Slows heart beat Promotes glycogen formation

Fig : Functions of Autonomic Neural System

Lung

Heart

Liver Stomach

Intestines

Pancreas

Adrenal gland

Genitalia

Bladder

Salivary glands Eye

Sympathetic division

Flow chart : Flow of information from receptors to effectors via CNS and PNS

Start

Central Nervous System

The central nervous system (CNS) consists of the brain and spinal cord and is responsible for integrating, processing, and coordinating sensory data and motor commands.

Peripheral Nervous System The

peripheral nervous system (PNS) includes all the neural tissue outside the CNS.

The sensory division of the PNS brings information to the CNS

from receptors in peripheral tissues and organs.

Somatic sensory receptors provide position,

touch, pressure, pain and temperature sensations.

Special sensory receptors provide

sensations of smell, taste, vision, balance and hearing.

Visceral sensory receptors

monitor internal organs.

Receptors are sensory structures that detect

changes in the internal or external environment.

includes

Information processing

includes the integration and distribution of information in CNS.

The motor division of the PNS

carries motor commands from the CNS to peripheral tissues and systems.

The somatic nervous system (SNS)

controls skeletal muscle contractions.

The autonomic nervous system (ANS) provides

automatic regulation of smooth muscle, cardiac muscle, glands, and adipose tissue.

Sympathetic division mobilises

body systems during activity (fight

or flight).

Parasympathetic division conserves

energy and promotes housekeeping functions during rest.

Effectors are target organs whose activities

change in response to neural commands.

New MCQs

1 Membrane adhering closely to the skull is

(a) arachnoid (b) endometrium

(c) piamater (d) duramater

2 Purkinje cells are present in

(a) medulla (b) hypothalamus

(c) cerebrum (d) cerebellum

3 Which cranial nerves has the maximum number of

branches?

(a) Vagus nerve (b) Trigeminal

(c) Facial nerve (d) Hypoglossal

4 How many pairs of cranial nerves are sensory?

5 Number of lumbar spinal nerves are

(a) 12 pairs (b) 8 pairs

(c) 1 pair (d) 5 pairs

6 Pineal body is present in

(a) diencephalon (b) rhombencephalon

8 Given is the diagram of human brain

Identify A, B, C and D correctly

(a) A-Corpus callosum, B- Hind brain, C- Medulla oblongata, D-Cerebral aqueduct

(b) A-Thalamus, B-Cerebellum, C- Spinal cord, D- Brain stem(c) A-Corpus callosum, B- Cerebellum, C- Medulla oblongata, D- Pons(d) A- Cerebrum, B-Brain stem, C- Spinal cord, D- Medulla oblongata

9 The inner parts of cerebral hemispheres and a group of associated deep structures like amygdala, hippocampus, etc form a complex structure called

(a) arbor vitae (b) limbic system(c) corpora quadrigemina (d) reticular system

A

B C

D

10 The 3rd, 6th and 7th cranial nerves are

(a) oculomotor, abducens and facial

(b) oculomotor, trigeminal and accessory

(c) optic, facial and spinal accessory

(d) trochlear, abducens and vagus

11 Read the following statements carefully and select the

correct option

(i) The medulla is connected to the spinal cord

(ii) Medulla contains controlling centres for respiration,

cardiovascular reflexes and gastric secretion

(iii) Hypothalamus influences respiration

(iv) Corpora quadrigemina is concerned with hearing

(a) (i) and (iv) only (b) (ii) and (iii) only

(c) (iii) and (iv) only (d) (i), (ii) and (iii)

12 The grey matter of spinal cord is

(i) butterfly shaped and present outside the white matter

(ii) grey in colour in unstained preparation

(iii) matter lacking myelinated nerve fibres

(iv) contains interneurons

Correct statements are:

(a) (i) and (iii) only (b) (ii), (iii) and (iv) only

(c) (ii) and (iv) only (d) (i), (ii) and (iii) only

13 In a man, abducens nerve is injured Which one of the

following functions will be affected?

(a) Movement of the eyeball

(b) Movement of the tongue

(c) Swallowing

(d) Movement of the neck

14 Consider the following statements about the sympathetic

division of the ANS and choose the correct option

(I) All its neurons release norepinephrine as their primary

neurotransmitter substance

(II) All the cell bodies of its post-ganglionic neurons lie in

or near the organ innervated

(III) The cell bodies of its pre-ganglionic neurons lie in the

thoracic and lumbar regions

(a) I is true (b) II is ture

(c) III is true (d) I and III are true

15 Which of the following statements is correct for iter?

(a) It form a branching tree like core of white matter,

called arbor vitae

(b) It is a very narrow cavity, the cerebral aqueduct,

extending through the forebrain

(c) It is a very narrow cavity, the cerebral aqueduct,

extending through the midbrain

(d) It connects the pons varolii and cerebellum

16 Identify the ventricle of the brain

represented by A in the given diagram

(a) Third ventricle

in contrast to one neuron for parasympathetic signals(b) sympathetic fibres alone innervate organs in the abdominal cavity

(c) sympathetic fibres alone arise from the spinal cord (d) effects of the two divisions on the organs are usually antagonistic

(a) cholinergic (b) adrenergic(c) dopaminergic (d) GABA nergic

19 Limbic system is involved in(i) thermoregulation(ii) regulation of sexual behaviour

(iii) expression of emotional reactions (e.g., excitement,

pleasure, rage and fear)(iv) respiration

Choose the correct option

(a) (ii) and (iii) (b) Only (iii)(c) (i), (iii) and (iv) (d) (i), (ii) and (iii)

20 Which pair of nerve and organ innervation is incorrect?(a) Trochlear - Eye muscle(b) Vagus nerve - Abdominal viscera(c) Glossopharyngeal nerve - Taste buds(d) Hypoglossal nerve - Facial muscles

2 Which one of the following acts solely as an inhibitory neurotransmitter?

(a) Norepinephrine(b) Gamma (γ) amino butyric acid(c) Acetylcholine

4 How do parasympathetic neural signals affect the working

of the heart?

(a) Reduce both heart rate and cardiac output

(b) Heart rate is increased without affecting the cardiac output.(c) Both heart rate and cardiac output increase

(d) Heart rate decreases but cardiac output increases

(AIPMT 2014)

5 Which excitatory neurotransmitter is involved in the

transmission of impulse at the neuro-muscular junction?

(a) Epinephrine (b) Serotonin

(c) Acetylcholine (d) Glycine (WB JEE 2014)

6. Which area of cerebral cortex is responsible for the

(i) is released by sympathetic fibres

(ii) is released by parasympathetic fibres

(iii) increases the heart rate

(iv) decreases blood pressure

Which of the above statements are correct?

(a) (i) and (iii) (b) (ii) and (iii)

(c) (ii) and (iv) (d) (i) and (iv)

(NEET - Karnataka 2013)

8 A person entering an empty room suddenly finds a snake

right in front on opening the door Which one of the

following is likely to happen in his neuro-hormonal control

system?

(a) Sympathetic nervous system is activated releasing

epinephrine and norepinephrine from adrenal medulla

(b) Neurotransmitters diffuse rapidly across the cleft and

transmit a nerve impulse

(c) Hypothalamus activates the parasympathetic division

of brain

(d) Sympathetic nervous system is activated releasing

epinephrine and norepinephrine from adrenal cortex

(AIPMT Prelims 2012)

9 Parasympathetic ganglia are present in

(a) head and neck

(b) chains of lateral ganglia

(c) grey matter of thoracic and lumbar region of spinal cord

10 The optic lobes in humans are represented by the corpora

(a) bigemina (b) arenacea

(c) allata (d) quadrigemina (AMU 2012)

11 Integration of the visual, tactile and auditory inputs occurs

in the

(a) peripheral nervous system

(b) corpus callosum (c) limbic system

(d) medulla oblongata (e) midbrain (Kerala 2012)

12 Body posture, equilibrium and rapid muscular activities are

controlled by

(a) diencephalon (b) cerebellum

(c) olfactory lobes (d) hypothalamus

(Odisha 2012)

13 Third and fourth ventricles of the brain are connected by

(a) aqueduct of Sylvius (b) foramen of Monro

(c) foramen of Magnum (d) corpus callosum

15 Movement of tongue muscle is controlled by (a) facial nerve (b) trigeminal nerve(c) hypoglossal nerve (d) vagus nerve (WB-JEE 2011)

16 Which function will be lost due to damage of occipital lobe?

(a) Hearing (b) Speech(c) Vision (d) Memory (WB-JEE 2011)

17 The third ventricle of the brain is situated in the(a) base of telencephalon

(b) roof of metencephalon(c) roof of diencephalon (d) base of myelencephalon (AMU 2010)

18 Which of the following is not an effect of the sympathetic nervous system ?

(a) Dilation of pupil (b) Inhibition of peristalsis(c) Elevation of blood pressure (d) Stimulation for saliva secretion (AMU 2010)

19 Which of the following nerves innervates alimentary canal?

(a) Oculomotor (b) Abducens(c) Trigeminal (d) Vagus (Odisha 2010)

20 Parasympathetic nerves arise from which region of the nervous system?

(a) Thoracolumbar (b) Cervical(c) Craniosacral (d) Lumbar (UP-CPMT2010)

Assertion & Reason

The following questions consist of two statements each : assertion (A) and reason (R) To answer these questions, mark the correct alternative as directed below :

(a) If both A and R are true and R is the correct explanation

of A

(b) If both A and R are true but R is not the correct explanation

of A

(c) If A is true but R is false

(d) If both A and R are false

1 Assertion (A) : Hypothalamus regulates secretion of

neurohormones

Reason (R) : Hypothalamus links nervous system and

endocrine system

2 Assertion (A) : The space between arachnoid membrane

and pia-mater of brain is filled with cerebrospinal fluid

Reason (R) : Cerebrospinal fluid provides medium for

exchange of food materials and respiratory gases

3 Assertion (A) : All cranial nerves are sensory nerves.

Reason (R) : All cranial nerves carry impulses from receptors

to brain

4 Assertion (A) : The cerebral cortex makes up the grey

matter of brain

Reason (R) : Cerebral cortex has high concentration of non

medullated nerve fibres

5 Assertion (A) : Sympathetic preganglionic neurons are

adrenergic

Reason (R) : Sympathetic preganglionic neurons stimulate

adrenal gland to secrete adrenaline and noradrenaline

Short Answer Type Questions

1 Fill in the blanks:

(a) Paired rounded protrusions present on superior surface

of mid brain are _

(b) Cranial nerve originating from both brain and spinal

cord is

(c) Lateral ventricle of brain is connected to third ventricle

by _

(d) _ is the smallest cranial nerve and is

the largest cranial nerve

2 Write the functions of cerebrospinal fluid

3 Differentiate between cerebrum and cerebellum

4 Write the effects of sympathetic nervous system on heart,

pancreas, urinary bladder and sweat glands

5 Briefly describe the internal structure of spinal cord

6 Write a short note on cholinergic neurons

7 Identify the central lobes of brain associated with following

functions :

(a) Decoding and interpretation of sound, language and

smell

(b) Sensory perception of touch and pain

(c) Decoding and interpretation of visual information

Short Answer Type Questions

1 (a) corpora quadrigemina (b) accessory nerve(c) foramen of Monro (d) Trochlear, trigeminal

2 Functions of cerebrospinal fluid are:

(i) It acts as a shock absorber for the brain and spinal cord

(ii) It nourishes brain tissue by transporting constant supply

of food and oxygen

(iii) It also carries harmful metabolic wastes, drugs and other substances from the brain to the blood

(iv) Maintains a constant pressure inside the cranium inspite of variation in the pressure of blood in the cranial vessels

3 The differences between cerebrum and cerebellum:

(iii) Arbor vitae is absent in cerebrum

Arbor vitae is present in cerebellum

(iv) It contains various functional areas and is mainly concerned with intelligence, memory, etc

It maintains posture and equilibrium

4 Effects of sympathetic nervous system on different organs are as follows:

Heart – accelerates heart beatPancreas – inhibits secretionUrinary bladder – relaxes bladderSweat glands – increases secretion

5 The internal anatomy of spinal cord shows grey matter and white matter Grey matter is inner, butterfly shaped area and lacks myelin, thus, giving grey appearance Surrounding the grey matter is the white matter, with high concentration of myelinated nerve fibres, giving opaque white appearance The dorsal and ventral nerve root connect spinal nerve with spinal cord The dorsal nerve root consists of sensory axon and ventral nerve root contains motor axons

6 Cholinergic neurons release the neurotransmitter acetylcholine (Ach) In the ANS, the cholinergic neurons include (a) all sympathetic and parasympathetic preganglionic neurons, (b) sympathetic postganglionic neurons that innervate most sweat glands and (c) all parasympathetic postganglionic neurons The preganglionic fibres of both sympathetic and parasympathetic neural system are cholinergic

7 (a) Temporal lobe (b) Parietal lobe(c) Occipital lobe



CHAPTER-11 : TRANSPORT IN PLANTS

Multiple Choice Questions

1 The translocation of water in higher plants is always

(a) unidirectional (b) bidirectional

(c) multidirectional (d) both ‘a’ and ‘b’

2 Consider two cells A and B The cell has OP = 8 atm and

TP = 5 atm, while cell B has OP = 6 atm and TP = 2 atm

What changes do you suppose to observe in the cells?

(a) Development of higher DPD in cell A

(b) Reduction of wall pressure in both the cells

(c) Development of higher DPD in cell B

(d) Development of same DPD in both the cells

3 Read the following statements carefully and choose the

incorrect statements

I The total water content present in soil is called chresard

II The water available to plants is called holard

III Capillary water is the only water available to plant roots

IV The soil water unavailable to plants is called echard

(a) I and III (b) II and IV

(c) I and II (d) II, III and IV

4 Jams and jellies are preserved by addition of sugar because it

(a) kill bacterial and fungal spores

(b) cause plasmolysis of cells

(c) creates osmotic shock

(d) all of these

5 During transpiration, the stomata opens when guard cells(a) lose K+ ions (b) lose H+ ions

(c) gain entry of K+ ions (d) lose Cl– ions

6 Consider the following statements with reference

to translocation of mineral ions Choose the correct statements from the following

I Minerals are received by cells through active uptake

II Minerals pass through both xylem and phloem in an inorganic form

III Minerals are unloaded at fine vein endings through diffusion

IV All the minerals from older senescing parts are remobilised to young growing parts

(a) I, II and IV (b) I and III(c) III and IV (d) All of these

7 The food or carbohydrates formed in leaf are translocated through sieve tubes in the form of sucrose It appears most suitable for this purpose as

(a) it is a reducing sugar (b) chemically unstable (c) does not react with other substances

(d) all of these

8 Farmers can grow crops even in unirrigated areas or desert areas with the help of some chemicals Choose the correct chemical that can help the farmer to grow plants in such regions

(a) Gibberellin (b) Phenyl mercuric acetate(c) Arsenic emulsion (d) Cyanide

UNIT-IV : PLANT PHYSIOLOGY

Maximise your chance of success in NEET by reading this article This section is specially designed to optimise your preparation

by practising more and more It is a unit wise series having chapterwise question bank, allowing you to prepare systematically and become more competent

Recall question or single concept question – indicated by a single finger

Application question or question which requires 2 or 3 concepts - indicated by 2 fingers

Application question or question which requires 3 or more concepts - indicated by 3 fingers

9 Maximum root pressure is observed during

(a) drought and starvation

(b) rainy season in temperate habitat

(c) low temperature

(d) spring season in temperate habitat

10 Consider the following statements with reference to

guttation and choose the incorrect statements

I Guttation is exudation of water in the form of droplets

from the margins of leaves

II Guttated liquid is pure water

III Guttation may occur during any time in a day when

water is available in excess

IV Guttation takes places through special structures

called hydathodes

(a) I and II (b) II and III

(c) III only (d) I and IV

Match The Columns

11 Match the Column I with Column II

A Root pressure (i) Cell wall

B Transpiration pull (ii) Active water absorption

C Apoplast pathway (iii) Plasmodesmata

D Symplast pathway (iv) Passive water absorption

12 Match Column I with Column II (There can be more than

one match for items in Column I)

Column I Column II

A Stomata (i) Reduction in photosynthesis

B Hydathodes (ii) Abscisic acid

C Anti-transpirants (iii) Epithem

D Wilting (iv) Loss of turgidity

(vi) Exchange of gases (vii) Silicon emulsions

Passage Based Question

13 Complete the given passage with appropriate words or

phrases

(i)_ is directional movement of substances in plants The

translocation of organic substances occur over long

distances between (ii)_ and _(iii)_ Since, the relationship

between the two is variable, it is (iv)_ When source and

sink lies on opposite sides, it shows _(v)_ The mechanism

of translocation of organic solutes is best explained by

_ (vi) _ It states that organic solutes move from region

of high to region of low osmotic pressure due to _ (vii) _

gradient A high osmotic concentration develops in _(viii)

of source, which absorb water and develop high turgor pressure This results in _(ix) of solutes in sink which maintains _(x)_ by converting soluble solutes into insoluble forms and water passes back into xylem

Assertion & Reason

In each of the following questions, a statement of Assertion (A)

is given and a corresponding statement of Reason (R) is given just below it Of the statements, mark the correct answer as :(a) If both A and R are true and R is the correct explanation of A(b) If both A and R are true but R is not the correct explanation of A.(c) If A is true but R is false

(d) If both A and R are false

and conifers

Reason : The tracheidal xylem is least affected by

gravitational pull under tension

movement of water through cells

Reason : Apoplast pathway is affected by the metabolic

state of root cells

transport of water soluble substances

Reason : Aquaporins transport substances against the

concentration gradient

rate of transpiration

Reason : A very high wind velocity results in closure of

stomata due to mechanical effect, drying and cooling

capacity

Reason : Lignin being hydrophobic, remains unaffected

by imbibition

Figure Based Questions

19 Consider the given figure and answer the following questions

(a) What is being tried

to deduce from given exprimental set-up?

(b) State the significance

of using eosine in the experiment

(c) How the colour travels from solution

to veins of leaf?

Leaves

Red coloured veins Shoot Beaker Eosine solution

20 Refer to the given figure showing stomatal apparatus and

answer the following questions

Chloroplast

Epidermal cell

C A B

(a) Identify the parts A, B and C.

(b) State any two functions of A.

(c) What is the role of ‘C’ in stomatal apparatus?

CHAPTER-12 : MINERAL NUTRITION

Multiple Choice Questions

1 Which of the following nutrients is requried by plants in

least quantity?

(a) Nickel (b) Molybdenum

(c) Copper (d) Zinc

2 Identify the set of nutrients that are involved in translocation

of organic substances in phloem

(I) Potassium (II) Boron

(III) Magnesium (IV) Calcium

(a) I and IV (b) II and III

(c) I and II (d) II, III and IV

3 Carefully read the following statements and choose the

correct statements from the options given below

I Hydroponics is the practice of growing plants in

nutrient enriched water, without soil

II Hydroponics is useful for cultivation of plants in areas

with thin, infertile and dry soils

III Hydroponics is not useful in controlling the soil

pathogens and problems of weeding

IV Only seasonal vegetables can be successfully grown

through hydroponics, but not flowering plants

(a) I and IV (b) II and III

(c) I, III and IV (d) I and II

4 The microorganism responsible for conversion of nitrates

to gaseous nitrogen is

(a) Nitrosomonas (b) Nitrocystis

(c) Micrococcus (d) Bacillus ramosus.

5 The micronutrient ‘zinc’ acts as an activator of

(a) alcohol dehydrogenase

(b) amino acid oxidase

(c) phosphoenol pyrvuate carboxylase

(d) Irreversibly binds to oxygen so as to inhibit nitrogen fixation

7 Identify the elements that causes toxic effect upon protoplasm.(a) Carbon, sulphur, oxygen

(b) Arsenic, copper, mercury(c) Copper, calcium, phosphorus (d) Silicon, copper, arsenic

8 Metabolic energy utilised in uptake of ions is demonstrated by(a) decreased ion uptake in presence of oxygen (b) increased uptake in presence of NAD(c) increased ion uptake in presence of oxygen (d) increased ion uptake in presence of ATP

9 Consider the given statements regarding mineral toxicity and choose the incorrect pair of statements

I Critical toxic concentration is same for all micronutrients in different plants

II Brown spots surrounded by chlorotic veins in leaf is due to magnesium toxicity

III Magnesium toxicity reduces the uptake of iron and calcium

IV The excess of manganese causes deficiency of iron, magnesium and calcium

(a) I, II and III (b) III and IV(c) I and IV (d) None of the above

10 Corky core in apples is caused due to deficiency of nutrient

(c) boron (d) chlorine

Match The Columns

11 Match the nutrients in Column I with their deficiency symptoms or diseases given in Column II

A Iron (i) Blossom end rot of tomato

B Potassium (ii) Disintegration of plastids

C Calcium (iii) Sterile flowers

D Nickel (iv) Inhibition of chloroplast formation

E Manganese (v) Leaf tip necrosis

12 Match the Column I with Column II (There can be more than one match for items in Column I)

Column I Column II

A Free living N2 fixing (i) Anabaena

bacteria

B Symbiotic N2 fixing (ii) Trichodesmium

Passage Based Question

13 Complete the given passage with appropriate words or

phrases

The most important source of nitrogen in plants is (i) ,which

though accumulates in cell sap but cannot be utilised

by plants as such It is therefore reduced by enzyme

(ii) to nitrite Another metalloflavoprotein, called

(iii) acts on nitrite It requires NADPH (reducing power) and

(iv) to produce (v) The product is not released, rather

combines with organic acids like oxaloacetic acid to form

_(vi)_ Ammonia reacts with glutamic acid in the presence

of enzyme _(vii)_ and ATP to form an amide called _(viii)_

The transfer of amino group of one amino acid with keto

group of keto acid is called _(ix)_ _(x)_ is the primary

amino acid involved in amino group transfer

Assertion & Reason

In each of the following questions, a statement of Assertion (A)

is given and a corresponding statement of Reason (R) is given

just below it Of the statements, mark the correct answer as :

(a) If both A and R are true and R is correct explanation of A

(b) If both A and R are true but R is not the correct explanation of A

(c) If A is true but R is false

(d) If both A and R are false

calcium and sulphur appear first in young tissues and

exhibit similar balancing functions

Reason : Magnesium and potassium minimise the toxic

effects of heavy elements

of transport of water

Reason : Active absorption of mineral salts involves

carrier compounds present in plasma membrane of cells

colour

Reason : The enzyme dinitrogenase is present in plant

cell wall

Figure Based Questions

19 Carefully observe the given figure and answer the following questions

Motor-driven rotor

Nutrient mist chamber

Nutrient solution

(a) Name the process being depicted in the figure (b) How do the plants receive nutrients in absence of soil? (c) Name a few plants successfully grown by given process.

20 Consider the figure showing stages of nodule formation, and answer the given questions

Bacteria

Vesicle containing rhizobia

(a) Identify the stages being shown through A, B, C and D (b) Name the bacteria and a plant showing this type of

relationship

(c) Which enzyme and elements participate in the process

occuring inside the nodule?

CHAPTER-13 : PHOTOSYNTHESIS IN HIGHER PLANTS

Multiple Choice Questions

1 Chloroplast will show the maximum concentration of

(a) fructose

(b) RuBP carboxylase

(c) starch

(d) 3-PGA

2 Study the following statements regarding chl a molecule.

(i) Molecular formula of chl a is C55H72O5N4Mg

(ii) It is the primary photosynthetic pigment

(iii) In pure state, it is red in colour and thus, it absorbs

more blue wavelength of light than the red

wavelength

(iv) It is soluble in water as well as petroleum ether

Which of the above statements is/are incorrect?

(a) (i) and (iii) (b) (iii) and (iv)

(c) (iii) only (d) (iv) only

3 Choose the correct pair describing the location of

photosystems

(a) PS I – appressed regions of granal thylakoids

(b) PS II – stromal thylakoids

(c) PS I – non-appressed parts of granal thylakoids

(d) PS II – partition regions of stromal thylakoids

4 Consider the following statements related to photosynthetic

pigments and identify the incorrect ones

I Chlorophylls are the primary photosynthetic pigments

II The pigment phycoerythrin imparts red colour to

tomatoes and chillies

III The yellowish colour of autumnal foliage is due to

phycobilin pigments

IV Carotenes act as accessory pigments as they help in

trapping most of the light energy

(a) I and III (b) I and II

(c) II, III and IV (d) All of these

5 Which organism possesses a single photosystem with

reaction centre similar to PS I?

(a) Blue green algae

(b) Cryptomonads

(c) Red algae

(d) Rhodopseudomonas

6 Identify the correct statement regarding photorespiration

(a) It is very useful process occurring in tropical plants

(b) It occurs only when both temperature and oxygen is low

(c) It protects the plant from photo-oxidative damage

(d) It helps in conserving energy when stomata gets

closed due to water stress

7 Given graph represents the absorption spectra of three

photosynthetic pigments, chl a, chl b and β-carotene

(b) Chl a and chl b absorb maximum light in blue and red

wavelengths of light

(c) Both (a) and (b) (d) None of these

8 The phenomenon of solarisation in plants occurs due to (a) reduction in hydration and closure of stomata(b) oxidation of photosynthetic pigments and enzymes(c) decline in rate of photosynthesis

(d) Bundle sheath cells have primary CO2 acceptor-PEP

10 How many molecules of ATP and NADPH will be consumed

by a maize plant to produce 1 glucose molecule?

Match The Columns

11 Match the names of scientists in Column I with their discoveries in Column II

A Peter Mitchell (i) Light and dark phases

B Daniel Arnon (ii) Z-scheme of photosystems

C Caventou (iii) Chemiosmotic hypothesis

D Hill and Bendall (iv) Discovered chlorophyll

E Emerson and Arnold (v) Photophosphorylation

12 Match the Column I with Column II (There can be more

than one match for items in Column I)

Column I Column II

A C3 cycle (i) Succulents

B C4 cycle (ii) Cyclic photophosphorylation

(viii) Kranz anatomy

Passage Based Question

13 Complete the given passage with appropriate words or

phrases

The primary CO2 acceptor of C3 plants is (i) It binds with

(ii) as well as with (iii) This affinity for latter causes a

‘glitch’ in photosynthesis called as (iv) Certain plants have

evolved alternate methods to avoid this process and fix CO2

by (v) ,as in sugarcane These plants exhibit characteristic

(vi) and enzyme (vii) to fix CO2 The Calvin cycle in such

plants takes place in (viii) cells This costs the cell extra

energy Therefore, plants in very hot climates have adopted

another pathway namely (ix) These plants conserve water

as they keep their (x) closed during day and open them

only at night.,

Assertion & Reason

In each of the following questions, a statement of Assertion (A)

is given and a corresponding statement of Reason (R) is given

just below it Of the statements, mark the correct answer as :

(a) if both A and R are true and R is the correct explanation of A

(b) if both A and R are true but R is not the correct explanation

of A

(c) if A is true but R is false

(d) if both A and R are false

b show that they absorb maximum light in green and red

wavelength range

Reason : Chlorophylls show blue, violet fluorescence.

of CO2, twelve molecules of NADPH and 18 ATP are

consumed

Reason : Light reaction results in formation of ATP and

NADPH

in their epidermal cells

Reason : Anthocyanins are accessory photosynthetic

pigments

in oxygen evolving complex, attached to inner surface of thylakoid membrane

Reason : The release of oxygen cannot take place in

absence of Mn2+, Ca2+ and Cl– ions

temperature, aridity and salinity

Reason : RuBisCO acts purely as carboxylase.

Figure Based Questions

19 Consider the given figure and answer the following questions

(a) What do X, Y and Z represent on the three curves in

the above given figure?

(b) Sometimes deviations are observed in Blackman’s

law and transitional curves are obtained What could

be the probable reason for this?

(c) Mention the condition where light intensity and

temperature act as limiting factors in photosynthesis

20 Refer to the given figure and answer the following questions

(a) Identify the products marked A, B and C.

(b) Name the cycle being represented in the above

diagram Also, state its important steps

(c) What is the site of carbon fixation by this cycle in C4

plants?

CHAPTER-14 : RESPIRATION IN PLANTS

Multiple Choice Questions

1 If the volume of CO2 liberated during respiration is more

than the volume of O2, the respiratory substrate is identified

(a) Conversion of succinyl CoA to succinic acid

(b) Conversion of succinic acid to fumaric acid

(c) Conversion of α-ketoglutarate to succinyl CoA

(d) Conversion of fumaric acid to malic acid

3 Which of the given observations most strongly support the

view that mitochondria contain electron transfer enzymes

aggregated into compact associations?

(a) Isolation of a contractile protein from mitochondria

which is capable of utilising ATP

(b) Disruption of mitochondria yields membrane

fragments which are able to synthesise ATP

(c) Presence of numerous folds on inner wall of

mitochondria

(d) All of these

4 If a molecule of pyruvic acid is subjected to anaerobic

respiration to produce lactic acid, there would be

(a) gain of 3 ATP molecules

(b) gain of 6 ATP molecules

(c) gain of 2 ATP molecules

(d) gain of 10 ATP molecules

5 The fruits stored in refrigerator or cold storage maintain

their flavour and taste for longer period due to

(a) presence of excess of carbon dioxide

(b) non-availability of oxygen

(c) slower rate of respiration

(d) presence of excess humidity

6 Consider the following statements regarding respiration in

plants and choose the correct ones

I In plants, gaseous exchange takes place only through

stems

II Plants respire at rates lower than animals

III Leaves are adapted to synthesise food and not for

respiration

IV Loosely arranged parenchymatous cells in stem and roots of plants provide network of gaseous exchange

V Plants do not have respiratory organs

(a) I, III and V (b) II, IV, V(c) II and III only (d) I, II, III and IV

7 Which of the following enzymes is inhibited by excess of ATP production during respiration?

(a) Hexokinase (b) Pyruvic decarboxylase(c) Aldolase (d) Phosphofructokinase

8 Read the given statements carefully and choose the incorrect ones

I The stepwise release of chemical energy cannot be always trapped in ATP molecules

II Cellular temperature becomes very high during cellular respiration

III ATP acts as a phosphorylating agent for activating certain metabolites like sugars

IV ATP cannot make energy available at a spot away from area of release of energy

(a) I, III and IV (b) II and III(c) I, II and IV (d) All of these

9 Substrate level phosphorylation in glycolysis occurs when(a) Glyceraldehyde-3-phosphate changes to 1,3-biphos-phoglycerate

(b) 1, 3 biphosphoglycerate changes to 3 phosphoglycerate(c) 3 phosphoglycerate changes to 2 phosphoglycerate (d) 2 phosphoglycerate changes to phosphoenol pyruvate

10 Identify the correct sequence of steps in glycolysis.(a) Glucose 6-phosphate → 1,3 biphosphoglycerate

→ 3-PGAL (Glyceraldehyde 3-phosphate) → PEP (Phosphoenol pyruvate)

(b) Glucose 6-phosphate → 3-PGAL → 3-PGA phoglycerate) → PEP (Phosphoenol pyruvate)(c) Glucose 6-phosphate → PEP (Phosphoenol pyruvate)

(3-phos-→ 3PGA (3-phosphoglycerate) (3-phos-→ 3-PGAL(d) Glucose 6-phosphate → 3-PGAL → 1,3 biphosphogly-cerate → 3-PGA (3-phosphoglycerate)

Match The Columns

11 Match Column I with Column II

A Isocitrate (i) 2C compound

B Malate (ii) 3C compound

C α-ketoglutarate (iii) 4C compound

D Acetyl CoA (iv) 5C compound

E Phosphoglycerate (v) 6 C compound

12 Match the reaction intermediates of Krebs’ cycle in Column

I with the products they give rise to in Column II (There

can be more than one match for items in Column I)

Column I Column II

A Acetyl CoA (i) Glutamate

B α-ketoglutarate (ii) Glyceraldehyde 3-phosphate

C Succinyl CoA (iii) Isoprenoids

D Glycerol (iv) Chlorophyll

Passage Based Question

13 Complete the given passage with appropriate words or

phrases

A single turn of Krebs’ cycle produces one molecule of (i),

one molecule of (ii) , two molecules of (iii) and three

molecules of (iv) For each glucose molecule processed,

there are (v) turns of the cycle Seven of the eight

steps of citric acid cycle take place within the (vi) of

mitochondrion, while the production of (vii) takes place

elsewhere Electrons enter the electron transport system

as parts of hydrogen atoms attached to (viii) and (ix)

The energy released during passage of electrons from one

carrier to another is used to (x) protons out of matrix into

intermembrane space

Assertion & Reason

In each of the following questions, a statement of Assertion (A)

is given and a corresponding statement of Reason (R) is given

just below it Of the statements, mark the correct answer as :

(a) if both A and R are true and R is the correct explanation of A

(b) if both A and R are true but R is not the correct explanation

of A

(c) if A is true but R is false

(d) if both A and R are false

of respiratory substrate in absence of oxygen

Reason : Anaerobic respiration occurs only in

microorganisms and not in higher animals

long in higher organisms as it depletes more substrate,

so, that little is left for growth and repair

Reason : Anaerobic respiration powers active absorption

of minerals and protoplasmic streaming in higher

organisms

gradient across inner mitochondrial membrane

Reason : Energy released during passage of electrons

from one carrier to next, pumps H+ from matrix side

of inner mitochondrial membrane to its outer surface creating proton gradient which establishes electrical potential across it

and serve as biologically useful energy

Reason : The last two phosphate radicals of ATP are

attached by high transfer potential bonds, capable of releasing around 8.15 Kcal/mole of energy

more than one

Reason : The respiratory substrates in germinating seeds

are mainly carbohydrates

Figure Based Questions

19 Refer to given figure and answer the following questions

(a) What is the objective of the above experimental set

up?

(b) What can be inferred from the changes in set up after

sometime?

(c) Does anaerobic respiration always release CO2?

20 Consider the given figure and answer the following questions

(a) From the above given figure, identify the components A,

B, C and D

(b) Name the complexes involved in electron transfer in

the above described ETC

(c) State the site and enzyme required for ATP synthesis

How the enzyme becomes active?

CHAPTER-15 : PLANT GROWTH AND DEVELOPMENT

Multiple Choice Questions

1 High concentration of synthetic auxin is usually applied

for

(a) regulating growth of shoots

(b) controlling weeds

(c) elongation of reduced stems

(d) preventing the growth of apical shoots

2 Identify the hormone responsible for promoting development

of male flowers, even on female (monoecious) plants

(a) Auxin (b) Cytokinin

(c) Gibberellin (d) Ethylene

3 If a plant produces flowers on alternating exposure to

4 hours light and 2 hours darkness in a 24 hours cycle, it

should be a

(a) short day plant

(b) long-short day plant

(c) short-long day plant

(d) long day plant

4 Besides regulating photoperiodic responses in plants,

phytochrome also contributes in

(a) seed germination

(b) abscission

(c) photomorphogenesis

(d) both (a) and (c)

5 Consider the following statements and choose the correct

ones

I Heterophylly is the occurrence of different types of

leaves on the same plant in different environmental

conditions or growth phases

II The ability to change the structures developing in

different phases of growth is called plasticity

III Intrinsic plasticity is found in emergent hydrophytes

IV In plants, like Larkspur, the juvenile leaves are broadly

lobed while mature leaves are pinnately divided

(a) I, II and III (b) I and III

(c) I, II and IV (d) All of these

6 Senescence, an active cellular process in the growth and

functioning of a flowering plant is indicated in

(a) vessels and tracheid differentiation

(b) annual plants (c) floral parts

8 Choose the incorrect statement for phytochrome

(a) PFR form changes to PR by absorbing 660nm light

(b) PR form changes to PFR by absorbing 660nm light

(c) Phytochrome is blue coloured cytoplasmic protein

chromo-(d) It takes part in photomorphogenesis

9 Carefully read the statements related to vernalisation and choose the correct statements

I Vernalisation helps in increasing the vegetative period of plant

II It increases yield, resistance to cold and some diseases

III Kernel wrinkles of Triticale are removed by vernalisation.

IV The stimulus for vernalisation is perceived only by meristematic cells

(a) I and III only (b) II only(c) II, III and IV (d) IV only

10 Which of the following is the correct difference between auxin and gibberellin?

(a) Gibberellin transport is basipetal whereas auxin transport is both basipetal and acropetal

(b) Auxin has feminising effect in some plants whereas gibberellin has masculinising effect in some plants

(c) Auxin mobilises food reserve during seed germination whereas gibberellin has no such effect

(d) Auxin promotes flowering in long day plants whereas natural gibberellin has no such effect

Match The Columns

11 Match the Column I with Column II

A Auxin (i) Fruit ripening

B Gibberellin (ii) Prolonged shelf life

C Cytokinin (iii) Cell enlargement

D Abscisic acid (iv) Dormancy of buds

12 Match the Column I with Column II (There can be more

than one match for items in Column I)

Column I Column II

A Long day plants (i) Bryophyllum

B Short day plants (ii) Sunflower

C Short-long day plants (iii) Campanula medium

D Long-short day plants (iv) Spinacea oleracea

E Day neutral plants (v) Chrysanthemum

Passage Based Question

13 Complete the given passage with appropriate words or

phrases

Growth and various developmental processes of plants are

found to be regulated by two or more (i) acting (ii) or (iii)

Cell division is promoted by synergistic action of (iv) and

(v) Excess of auxins cause (vi) while excess of cytokinins

promote (vii) in callus On the other hand, auxins and

(viii) have feminising effect on plants but (ix) promote

maleness in plants Cambial activity requires auxins but is

checked by (x)

Assertion & Reason

In each of the following questions, a statement of Assertion (A)

is given and a corresponding statement of Reason (R) is given

just below it Of the statements, mark the correct answer as :

(a) if both A and R are true and R is the correct explanation of A

(b) if both A and R are true but R is not the correct explanation

of A

(c) if A is true but R is false

(d) if both A and R are false

direction through xylem

Reason : Roots are the major source of cytokinin

synthesis

amino acid tryptophan

Reason : Ethylene helps in ripening and dehiscence of

fleshy fruits

autumn

Reason : The plant requires long photoperiods for floral

initiation and short photoperiods for blossoming

for flowering stimulus by a previous cold treatment

Reason : The stimulus of vernalisation can be perceived

by any cell of the plant

increased by application of mixture of GA4 and GA7

Reason : GA7 delays senescence in plants

Figure Based Questions

19 Refer to given figures showing leaves of Ranunculus

(buttercup) and answer the following questions

(a) What does the leaves A and B in the above given

(b) Give one example each of plant A, B and C.

(c) State the difference between short-long day plants

and long-short day plants

Contd on page no 64

Although there are differences in structure and forms of different animals, yet there are

common fundamental features in various individuals in relation to the arrangement of cells,

body symmetry, nature of coelom, patterns of digestive, excretory, circulatory or reproductive

systems These features form basis of animal classification

BASIS OF ANIMAL CLASSIFICATION

Four levels of organisation found in animals are:

s

Organ-system level

Tissues develop into organs and organs form organ

systems, e.g., from aschelminthes to chordates.

Cell Aggregate Plan

Body consists of cluster of

cells E.g., sponges

Tube within-Tube Plan

The body has two tubes, one formed

by body wall and second formed within it by digestive tract.

Blind Sac Plan

The body has single cavity with one opening, serving as both mouth and anus

E.g., coelenterates and flatworms

Protostomic

Mouth of digestive tract develops first

E.g., roundworms, molluscs and arthropods

Anus of digestive tract develops first

E.g., echinoderms, chordates

Body symmetry is the similarity of parts in different regions and directions of the body.

s

Spherical symmetry: Body of individual can be divided into similar halves by any plane passing through centre E.g., sponges

Bilateral symmetry: Body having paired organs, present on two sides of central axis, divided into two halves by single plane only

E.g., Many invertebrates and all vertebrates.

Radial symmetry: Body divisible into equal halves by any plane passing through centre from top to bottom E.g., Some sponges, cnidarians,

Embryos with two germinal layers, ectoderm and endoderm An undifferentiated

mesoglea is present between two layers E.g., poriferans, cnidarians.

Triploblastic animals

Embryos with three germinal layers; ectoderm, mesoderm and

endoderm E.g , embryos from phylum platyhelminthes to chordates.

Animals on the basis of Germ Layers

Animals are divided into three main groups on the basis of coelom (body cavity):

s

Pseudocoelomates

Body cavity called pseudocoelom derived from blastocoel

of embryo E.g., roundworms.

Mesoderm arises from wall of embryonic

gut E.g., echinoderms and chordates.

Schizocoelom

Develops as split in mesoderm E.g.,

annelids, arthropods, molluscs.

Animals on the basis of Coelom

EXCLUSIVE FEATURES OF MAJOR PHYLA

PHYLUM PORIFERA (The Sponges)

Body wall consists of three layers:

s

(i) Outer pinacoderm, consists of flattened pinacocytes and oval porocytes.

(ii) Inner choanoderm, having specialised flagellated collar cells or choanocytes, and

(iii) Gelatinous non-cellular mesenchyme in between It consists of skeletal elements and amoebocytes.

Canal system system consists of pores and canals for ingress and egress of water currents In sponges, three types of canal systems are

s

found:

(i) Asconoid canal system- simplest type, e.g., Leucosolenia

(ii) Syconoid canal system- more complex than ascon type e.g., Sycon.

(iii) Leuconoid- Most complex canal system, found in Spongilla.

Development includes free swimming

s amphiblastula (in Sycon) and parenchymula (in Leucosolenia) larvae.

Classification : Phylum Porifera is divided into three classes

2 Hexactinellida Siliceous spicules with six rays Euplectella (The venus flower basket),

Hyalonema (The glass rope sponge)

3 Demospongiae Skeleton of spongin fibres or spongin fibres

with siliceous spicules

Euspongia (bath sponge), Cliona (boring sponge), Spongilla (fresh water sponge)

PHYLUM CNIDARIA

B

s ody wall comprises of outer epidermis, inner gastrodermis and non-cellular

gelatinous mesoglea between two layers

Epidermis consists of

s cnidoblasts (stinging cells), cnidoblast has nematocyst

(stinging organ) for defence and offence

Statocyst

s , a sense organ for balance, is developed for first time in Cnidaria

Holoblastic cleavage:

planula, scyphistoma and ephyra larvae are found

Metagenesis:

s In Obelia, polyps reproduce medusae asexually and medusae

form polyps sexually, such alternation of sexual and asexual phase is called

metagensis

Physalia (The Portuguese-man-of-war): Exhibits polymorphism and division of labour Three types of zooids and tentacles are

found hanging down below pneumatophore:

(a) Dactylozooids - organ of defense, secrete neurotoxic poison for catching food.

(b) Gastrozooids - nutritive zooids, and (c) Gonozooids - reproductive zooids.

PHYLUM CTENOPHORA (The Comb Jellies or Sea Walnuts)

Ctenophores show

s bioluminescence, the property of living organisms to emit light.

External surface of body have comb like 8 ciliary plates, called

Nematocysts are absent Instead, special adhesive and sensory cells, called

for capturing food and prey

Development includes

Examples :

s Pleurobrachia, Beroe.

PHYLUM PLATYHELMINTHES (The Flat worms)

The flat worms are mostly parasites, but some are free-living

s

Excretion through

s flame cells (solenocytes/protonephridia).

Larval stages in life cycle of liver fluke are

hexacanth and cysticercus larvae are found

Divided into three classes on the basis of mode of life

Peculiar features of parasitic platyhelminthes:

(i) The thick tegument (body covering) resistant to the host’s digestive enzymes and anti-toxins

(ii) Adhesive organs like suckers in flukes and the hooks and suckers in tapeworms for a firm grip on or in the host’s body

(iii) Loss of locomotory organs and sense organs

(iv) Absence of digestive organs in tapeworms as digested and semidigested food of the host is directly absorbed through the body

surface

PHYLUM ASCHELMINTHES (The Roundworms)

Body wall consists of nonliving, resistant cuticle,

s syncytial epidermis and muscle layer (longitudinal muscles only).

Sense organs include (i)

s Papillae - tactile in function (ii) Amphids - chemoreceptors (iii) Phasmids - glandulosensory in nature.

Indirect development includes following larval stages-

Wuchereria (filarial worm) and rhabditiform larva in Ascaris and Enterobius.

Ascaris lumbricoides - An endoparasite of small intestine of human beings.

Table: Differences between male and female Ascaris

A cloaca, for receiving anus and genital opening

is present The cloaca opens outside through

cloacal aperture

There are separate anus and genital apertures No cloaca is present

Two equal chitinous spicules (pineal setae)

Wuchereria- (The filarial worm) - An endoparasite in lymphatic vessels and lymph nodes of human beings (primary host) The mosquito

(Culex) is an intermediate host It causes elephantiasis (= Filariasis), in which limbs or other body parts grow to enormous size.

PHYLUM ANNELIDA (The segmented animals)

Metameric

segmentation-s Body divided externally (by annuli) and internally (by transverse septa) into true segments or metameres

Presence of

s closed blood vascular system Blood is red due to presence of pigment haemoglobin or erythrocruorin

Excretory system consisting of metamerically disposed coiled tubes, called

Receptors include

s tactile receptors (sensitive to touch), gustatoreceptors (taste receptors) and photoreceptors (sensitive

to light) Some forms have statocysts (balancing organs).

Mostly show direct development but indirect development includes

PHYLUM ARTHROPODA (Animals with jointed feet or appendages)

Body is covered with thick, tough, non-living chitinous cuticle, which forms exoskeleton Comprises of

Respiratory organs are

s gil ls or book gills in aquatic forms and tracheae or book-lungs in terrestrial forms.

Excretory organs are either

Classification : The Phylum Arthropoda is divided into seven classes

1 Crustacea Body divisible into

cephalo-thorax and abdomen

2 pairs of antennae and a pair of stalked

2 Chilopoda Body divisible into head and

3 Diplopoda Body is divided into head,

thorax and abdomen

Single pair of antennae Each thoracic segment bears a pair of legs (except first segment) Each abdominal segment has two pairs of legs

Julus (Millipede)

4 Insecta Body is divided into head,

thorax and abdomen

A pair of antennae and a pair of compound eyes Thorax has 3 segments with 3 pairs of legs and 2 pairs of wings

Silver fish, cockroach, bed bug, wasp etc

5 Arachnida Body divisible into

cephalo-thorax and abdomen

Cephalothorax bears simple eyes and

6 pairs of appendages (one pair of chelicerae, one pair of pedipalpi and four pair of legs) Antennae are absent

Scorpion, spider, tick, mite

6 Merostomata Body divided into

cephalo-thorax and abdomen

5-6 pairs of abdominal appendages with book gills Limulus (King crab) living fossil

7 Onychophora Single pair of antennae, eyes and jaws Peripatus (Connecting link between

Annelida and Arthropoda)

Economically important insects- Apis (Honey bee), Bombyx (silkworm), Laccifer (lac insect)

Vectors- Anopheles, Culex and Aedes (mosquito) Gregarious pest - Locusta (locust)

PHYLUM MOLLUSCA (Soft bodied animals)

Body of molluscs is unsegmented with distinct head, muscular foot and visceral hump

s

Shell

s secreted by mantle is made up of calcium carbonate

Mantle

s (Pallium) is thin, fleshy fold of dorsal body wall more or less covering the body

Blood is usually blue due to presence of a copper containing blue respiratory pigment

Sense organs are

s statocysts (balancing organs) and osphradium for testing chemical and physical nature of water.

Oviparous and indirect development includes

(monas- one, plax-plate, pherein-bearing)

The shell is cup or spoon-shaped E.g., Neopilina.

Gastropoda

Shell made up of one piece The early embryo is symmetrical but during development, the body twists showing torsion, so that the body becomes asymmetrical This class includes largest number of molluscs E.g., Pila, Doris, Limax, Limnaea, Patella, Helix.

Cephalopoda

Head and foot regions are combined and modified into structure

cephalopod or head foot having eyes and eight tentacles Shell

may be external (Nautilus), internal (Sepia) or absent (Octopus).

Amphineura

Non-ganglionated nerve ring present around mouth with two

pairs of interconnected nerve cord E.g., Chaetopleura (Chiton).

Phylum Mollusca

Divided into six classes

PHYLUM ECHINODERMATA (Spiny skinned animals)

madreporite is present in this system The pores of the madreporite

allow water into the system Most peculiar and interesting role of

water vascular system is to bring out locomotion by providing hydraulic

pressure mechanism

Tube feet help in anchoring the body to the substratum, capturing and

s

handling food and respiratory exchange of gases through thin walls

Echinoderms bears spines and

s pedicellariae Spines are protective in

function while the pedicellariae keep the body surface clear of debris and

minute organisms

Classification

Phylum Echinodermata

Divided into five classes

Echinoidea (Sea urchins)

Globular or disc like body Biting and chewing apparatus with

teeth called Aristotle’s Lantern is present Ambulacral grooves

are absent Pluteus and Echinopluteus larva E.g., Echinus (Sea

urchin), Clypeaster (cake urchin).

Asteroidea (Star fishes or sea stars)

Body star like, five arms not sharply marked off from central disc

Larval forms are Bipinnaria and Brachiolaria E.g., Asterias

(starfish), Pentaceros.

Holothuroidea (Sea cucumbers)

Elongated and cylindrical body Ambulacral grooves, spines and

pedicellaria are absent Larval forms are Auricularia and Doliolaria

E.g., Holothuria, Cucumaria.

Crinoidea (Sea lilies)

Body has central disc, which is attached to substratum Spines,

pedicellariae and madreporite are absent Doliolaria larva

They are commonly called feather stars or sea lilies E.g., Antedon (feather star).

Ophiuroidea (Brittle stars)

Star like body, arms sharply marked off from central disc

Ambulacral grooves and pedicellariae are absent Ophiopluteus

larva E.g., Ophiothrix, Ophiura.

s , Saccoglossus and Rhabdopleura

Balanoglossus (Acorn or Tongue worm)- Marine animal, lives in U-shaped burrows in bottom sand It feeds on organic matter ingested along with sand It is unisexual and shows external fertilisation

Dorsal hollow nerve cord

Always hollow and lies dorsal to the notochord

Pharyngeal gill slits

Gill slits on lateral sides of pharynx at some stage

All fossils had protective scales

or plates e.g., Climatius

This sub-phylum is also

s called Tunicata, because the adult

body is enclosed within leathery test or tunic formed of

cellulose like substance tunicin.

The notochord and dorsal tubular nerve cord are found only

SUB-PHYLUM VERTEBRATA OR CRANIATA

Have cranium around brain

s

Notochord present only in embryonic stage and is replaced

s

by vertebral column in adult forms

Nervous system consists of CNS, PNS and ANS

2 Minimum 4 letter word should be made.

3 In making a word, a letter can be used as many times as it appears in the box

4 Make at least 1 seven letter word.

Super Class Pisces (Bears fins)

Characteristics Chondrichthyes (Cartilaginous fishes) Osteichthyes (Bony fishes)

4 Mouth Ventrally placed Digestive tract leads into the

cloaca

The mouth is terminal Digestive tract leads into anus, cloaca is absent

7 Examples Torpedo (Electric ray), Trygon (Sting ray),

s dicondylic, i.e., two occipital condyles for articulation with vertebral column.

The respiratory organs are lungs, buccopharyngeal cavity, skin and gills

s

The heart is 3 chambered, having 2 auricles and 1 ventricle RBCs are oval, biconvex and nucleated

s

Fertilisation is external and are ovip

s d burrowing vertebrates, with rough and dry skin bearing epidermal scales

Respiration takes place through lungs

s

Heart consists of 3 chambers (2 auricles and a partially divided ventricle)

2 ventricles) RBCs are nucleated

Crocodiles are ammonotelic, turtles and alligators are ureotelic and lizards and snakes are uricotelic

and warm blooded animals.

Fore limbs are modified into

s

wings and hind limbs are

used for walking, swimming

or perching, etc

Skin is dry and without glands,

s

except for the presence of uropygial

gland (oil or preen gland) at the base of tail.

The upper and lower jaws are modified into beak, which

s

lacks teeth

The alimentary canal has additional chambers, the

gizzard The crop stores and soften the food while gizzard

helps in crushing and churning the food

Air sacs are connected to lungs for supplement respiration

s

Voice is produced by special organ syrinx.

Fully ossified (bony) endoskeleton with hollow, pneumatic

s

bones to reduce weight Sternum with a median keel for

attachment of flight muscles

Flightless Birds- Ostrich, Rhea, Emu, Kiwi, Cassowary, Penguin,

Dodo (extinct)

Flying Birds- Corvus (crow), Psittacula (Parrot), Columba

(Pigeon), Pavo (Peacock).

Sebaceous

and sudoriferous glands (sweat glands)

are present

Dentition is

s heterodont (different types of teeth), thecodont (embedded in sockets of jaws) and diphyodont

(develop twice during lifetime)

Possess muscular diaphragm, dividing trunk into thorax and

Examples - Oviparous - Ornithorhynchus (Duck billed

platypus), Echidna (Spiny anteater)

Viviparous - Macropus (kangaroo), Macaca (monkey), Rattus

(rat), Felis (cat), Panthera tigris (tiger) etc.

1 Free swimming larva of Sycon is

(a) amphiblastula (b) cydippid

(c) redia (d) parenchymula

2 Identify incorrectly matched pair

(a) Aurelia - Choanocytes

(b) Pleurobrachia - Colloblasts

(d) Planaria - Solenocytes

3 Which among the following organisms show metagenesis?

(a) Leucosolenia (b) Pleurobrachia

4 Acoelomate organism with bilateral symmetry is

(c) Spongilla (d) Fasciola.

5 Select the correct statement

(a) Indirect development of Schistosoma includes velliger

and trochophore larva

(b) Cartilaginous fishes have homocercal caudal fin and cycloid scales

(c) In Hemidactylus, eyelids are movable and nictitating

membrane is present

(d) Spider has 3 pairs of legs

6 Match the column I with column II

7 Ladder like nervous system is a peculiar feature of phylum(a) Cnidaria (b) Platyhelminthes

s ., Talpa micura (Mole), Crocidura murina (Musk

shrew), Sorex (Shrew), Paraechinus (Hedgehog).

Upper jaw contains two pairs of incisors while lower

s

jaw has one pair of them.

Pinnae are large.

s

Diastema occur.

s

E.g

s ., Oryctolagus (Rabbit), Lepus (Hare).

Forelimbs are modified into wings (patagium).

s Rattus (Rat), Mus musculus (Mouse).

Highly developed brain.

s ., Lemur, Tarsiers, Monkey, Apes, Man

Large canines, powerful jaws and claws.

s ., Panthera leo (Lion), Panthera tigris (Tiger),

Panthera pardus (Panther), Felis domestica (Cat),

Canis lupus (Wolf).

Insectivora

Carnivora Lagomorpha

Chiroptera

Primates Rodentia

Some of the principal orders of placental mammals are:

8 Fill in the blanks.

(i) Suckers and hooks are present in _

(ii) Preen glands are present in _

(iii) Salamander is _

(a) roundworms arthropods viviparous

(c) ctenophores molluscs ovoviviparous

(d) tapeworms birds viviparous

9 Identify A, B and C in the given table

Body segmentation like rings

Echinodermata Radial symmetry

with organ system level of organisation

C

(a) Tissue level organisation Annelida Water vascular

and biradial symmetry system

(b) Tissue level organisation Annelida Jointed

and bilateral symmetry appendages

(c) Cellular level organisation Aschel- Comb plates

and radial symmetry minthes for locomotion

(d) Organ system level Aschel- Flat body and

organisation and bilateral minthes suckers

symmetry

10 Jacobson’s organs for detecting odour are present in

(c) star fish (d) insects

11 How many cranial nerves are present in frog?

(a) 10 pairs (b) 12 pairs

(c) 14 pairs (d) 31 pairs

12 Which of the following is not a characteristic of urochordates?

(a) Retrogressive metamorphosis

(b) Body covered in leathery tunicin

(c) Notochord present in larval stages

(d) Copper containing blue respiratory pigment

13 The jawless fish is

14 Rhabditiform larva is present in

(a) Ascaris (b) Wuchereria

(c) Fasciola (d) Ancylostoma.

15 Protostomic plan is seen in(a) annelids and hemichordates(b) molluscs and arthropods(c) roundworms and urochordates(d) only chordates

16 Type of symmetry in which body of an individual can be divided into equal halves by any plane passing through centre from top to bottom is

(a) spherical symmetry (b) radial symmetry(c) bilateral symmetry (d) biradial symmetry

17 Indian earthworm belongs to class(a) Polychaeta (b) Hirudinea(c) Oligochaeta (d) Archiannelida

18 Match the following columns and select the correct option

Column-I Column-II Column-III

1 Holothuria p Cuttle fish a Porifera

2 Sepia q Sea anemone b Echinodermata

3 Cliona r Sea cucumber c Mollusc

4 Adamsia s Boring sponge d Coelenterata(a) 1-r-c, 2-p-a, 3-s-d, 4-q-b

(b) 1-s-b, 2-r-a, 3-p-c, 4-q-d(c) 1-r-b, 2-p-c, 3-s-a, 4-q-d(d) 1-q-b, 2-p-c, 3-r-a, 4-s-d

19 Excretory organs in Herdmania are

(a) coxal glands (b) neural glands(c) green glands (d) flame cells

20 Heart of Exocoetus comprises of

(a) one auricle and two ventricles(b) one auricle and one ventricle(c) two auricles and one ventricle(d) two auricles and two ventricles

1 Identify the type of flagellation in bacteria with a tuft of

flagella only at one end

(a) Monotrichous (b) Amphitrichous

(c) Cephalotrichous (d) Lophotrichous

2 Read the given statements and select the ones which are

true (T) or false (F)

(i) Mitochondria of eukaryotes have 80S ribosomes

(ii) DNA of E.coli is not associated with histone proteins.

(iii) Plasmids are self replicating, extra chromosomal

segments of single stranded, circular, naked DNA

(i) (ii) (iii) (i) (ii) (iii)

3 Identify A, B and C in the given table

Reducing Sugar β 1 – 4 glycosidic bond

between glucose and galactose

(a) Lactose Heteropolysaccharide Fruit sugar

(b) Sucrose Heteropolysaccharide Grape sugar

(c) Galactose Homopolysaccharide Cane sugar

(d) Maltose Oligosaccharide Milk sugar

4 The given figure represents

(a) early anaphase of mitosis

(b) late anaphase of mitosis

(c) anaphase of meiosis I

(d) anaphase of meiosis II

5 F+ or fertility factor controls formation of

(c) polysome (d) fimbriae

6 Identify incorrect statement for amino acid methionine.(a) It contains one amino group and one carboxylic group.(b) It can be synthesised by human body, and need not be present in the diet

(c) It is sulphur containing amino acid

(d) It is an essential amino acid

7 Read the following statements and select the option which correctly fills in the blanks

(i) stage of mitosis is called spireme stage

(ii) Most abundant protein of spindle fibre is .(iii) Division of cytoplasm in animal cells takes place by method

(a) (i)-Prophase, (ii)-actin, (iii)-cleavage(b) (i)-Prophase, (ii)-tubulin, (iii)-cleavage(c) (i)-Metaphase, (ii)-myosin, (iii)-cell plate(d) (i)-Metaphase, (ii)-actin, (iii)-cell plate

8 Match column I with column II and select the correct option

A SER (i) Help in movement of nuclei

B Chromoplasts (ii) Synthesis of glycogen

C Microtubules (iii) Formation of ribosome

D Nucleolus (iv) Provide colour to flowers

(a) A-(ii), B-(iii), C-(i), D-(iv)(b) A-(i), B-(iv), C-(ii), D-(iii)(c) A-(iii), B-(iv), C-(i), D-(ii)(d) A-(ii), B-(iv), C-(i), D-(iii)

This specially designed column enables students to self analyse their

extent of understanding of specified chapters Give yourself four

marks for correct answer and deduct one mark for wrong answer

Self check table given at the end will help you to check your

9 Carefully read the given statements.

(i) Enzyme protease is used for softening of bread and

meat

(ii) Lysozyme of tears is an exoenzyme, i.e., functional

outside living cells

(iii) Apoenzyme is non-protein part of conjugate enzyme

(iv) Prosthetic group is attached loosely to an apoenzyme

Choose the correct statements

(a) (i) and (iii) (b) (i) and (ii)

(c) (ii) and (iv) (d) (i), (iii) and (iv)

10 Which of the following features is unique to meiosis?

(a) Shortening and thickening of chromosomes

(b) Formation of spindle fibre

(c) Formation of nucleolus from satellite chromosome

(d) Pairing and recombination between homologous

chromosomes

11 Which of the following is correct statement?

(a) Lignin present in secondary cell wall, makes the wall

impermeable

(b) Cotransport of glucose and Na+ by facilitated diffusion,

occurs along the concentration gradient

(c) Acrosome of sperm is synthesised by Golgi complex

(d) Air vacuoles help in osmoregulation

12 Which amino acid is precursor of hormones thyroxine and

(a) Golgi apparatus (b) Endoplasmic reticulum

(c) Lysosome (d) Sap vacuole

14 Which region of tRNA contains CCA - OH group?

(a) AA - binding site (b) TψC loop

(c) Extra arm (d) DHU loop

15 During which stage of prophase I does recombination take

place?

(a) Diakinesis (b) Pachytene

(c) Diplotene (d) Zygotene

16 The protein with quaternary structure is

(a) haemoglobin (b) keratin

(c) tropomyosin (d) fibroin of silk

17 Cellular organelle formed by joint activity of endoplasmic

reticulum and Golgi complex

(a) Ribosome (b) Nucleus

(c) Vacuole (d) Lysosome

18 Match the column I with column II and select the correct

option (There may be more than one correct match for

column I)

A Starch (i) Storage protein

B Cholesterol (ii) Second chemical messenger

C Egg albumin (iii) Amylose

D cAMP (iv) Vitamin D precursor

(a) A-(iv), (viii); B-(i), (vii); C-(iii), (vi); D-(ii), (v)(b) A-(iii), (viii); B-(iv), (vi); C-(i), (vii); D-(ii), (v)(c) A-(iii), (vi); B-(i), (iv); C-(ii), (vii); D-(v), (viii)(d) A-(i), (viii); B-(ii), (v); C-(iv), (iii); D-(vi), (vii)

19 Secondary metabolite used as drug is(a) concanavalin A (b) ricin(c) abrin (d) vinblastin

20 At which stage of meiosis, do homologous pair of chromosomes gets separated?

(a) Anaphase I (b) Telophase I(c) Prophase I (d) Metaphase I

21 Organelle ‘X’ is the major centre of release of energy in aerobic respiration, but is absent in prokaryotes and anaerobic eukaryotes It can be stained differentially with Janus Green Identify the organelle X

(a) Nucleus (b) Mitochondria(c) Lysosome (d) Rough endoplasmic reticulum

22 Polytene chromosomes are not found in(a) salivary glands of insects

(b) animal spermatocytes(c) suspensor cells of embryo (d) antipodal cells of embryo sac

23 Ion which stimulates activity of salivary amylase is(a) Cl– (b) Fe2+ (c) Zn2+ (d) Na+

24 Which of the following sequence is correct in prophase I of the meiotic cell division?

(a) Leptotene, zygotene, diplotene(b) Zygotene, diplotene, diakinesis(c) Zygotene, pachytene, diplotene (d) Leptotene, pachytene, diplotene

25 Identify the type of bond present between monomers of polysaccharide

(a) CONH (b) C – O – C(c) O – HPO2– O (d) None of these

26 Fibril organisation in centriole and cilia is and respectively

(a) 9 + 0, 9 + 0 (b) 9 + 2, 9 + 0(c) 9 + 0, 9 + 2 (d) 9 + 2, 9 + 2

27 Which enzyme of Krebs’ cycle is not present in inner

chamber of mitochondria?

(a) Fumarase (b) Succinate dehydrogenase

(c) Aconitase (d) Malate dehydrogenase

28 Second checkpoint in cell cycle is

(a) G1 cyclin between G1 and S

(b) Mitotic cyclin between G2 and M

(c) Mitotic cyclin between M and G1

(d) G2 cyclin between S and M

29 Single membrane bound organelle showing phagocytic activity

(a) Lysosomes (b) Contractile vacuoles

(c) Oleosomes (d) Peroxisomes

30 Photosystem II in thylakoid membrane occurs in

(a) appressed parts of granal thylakoids

(b) stromal thylakoids

(c) nonappressed parts of granal thylakoids

(d) both (b) and (c)

31 Zygote is a/an

(a) dedifferentiated cell (b) post - mitotic cell

(c) differentiated cell (d) undifferentiated cell

32 The first division of meiosis is

(a) heterotypic or reductional division

(b) heterotypic or equational division

(c) homotypic or equational division

(d) homotypic or reductional division

33 Identify incorrectly matched pair

(a) Calcium pump in RBCs - Voltage gated ion channel

(b) Dialysis - Passive diffusion by open

(c) K+ – H+ exchange pump - Active transport

(d) Fat soluble substances - Simple diffusion

34 What are episomes?

(a) Free ribosomes in cytoplasm

(b) Single stranded, circular naked DNA

(c) Plasmids temporarily associated with nucleoid

(d) 4 - 8 ribosomes attached to single stand of mRNA

35 Identify the bouquet stage of meiosis

36 The cell organelle exhibiting polymorphism is(a) nucleus (b) vacuole(c) plastid (d) lysosome

37 The change of colour from green to reddish during the ripening of tomato is due to transformation of

(a) chromoplast to chloroplast(b) chloroplast to chromoplast(c) leucoplast to chloroplast(d) chromoplast to leucoplast

38 Who observed mitosis for the first time in plant cells ?(a) Strasburger (b) Boveri and Flemming(c) Sutton (d) Farmer and Moore

39 Select the correctly matched pair

(a) Elaioplasts – Protein containing colourless

(b) Residual lysosomes – Lysosomes formed by

(c) Glyoxysomes – Perform photorespiration,

(d) Chromoplast – Yellow coloured plastids

40 Read the given statements and select the correct option

Statement A : Water soluble vacuolar pigment anthoc- yanin attracts pollinating and dispersing agencies

Statement B : Anthocyanins provide colouration to

(c) Statement A is correct but B is incorrect

(d) Both statements A and B are incorrect

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