Bài giảng tiếng anh chuyên ngành sinh học

Biology is a natural science concerned with the study of life and living organism, including their structure, function, growth, origin, evolution, distribution, and taxonomy.. Subdiscip

UNIT 1: A VIEW OF LIFE

A READING TEXTS

I WHAT IS BIOLOGY?

Biology is a natural science concerned with the study of life and living organism, including their structure, function, growth, origin, evolution,

distribution, and taxonomy Biology is a vast subject containing many

subdivision, topics and disciplines Among the most important topics are five unifying principles that can be said to be the fundamental axioms of modern biology

1 Cells are the basic unit of life

2 New species and inherited traits are the product of evolution

3 Genes are the basic unit of the heredity

4 An organism regulate its internal environment to maintain a stable and constant condition

5 Living organism consume and transform energy

Subdisciplines of biology are recognized on the basis of the scale at which organism are studied and the methods used to study them: biochemistry examines the rudimentary chemistry of life: molecular biology studies the complex interactions of systems of biological molecules: cellular biology

examines the basic building block of all life, the cell; physiology examines the physical and chemical functions of the tissues, organs, and organs systems of

an organism; and ecology examines how various organisms interact and

associate with their environment

II THE CHARACTERISTICS OF THE LIVING ORGANISMS

1 Organisms are composed of cells

The cell theory , one of the fundamental unifying concepts of biology, states that all living organisms are composed of basic units called cells and of substances produced by cells Although they vary greatly in size and

appearance, all organisms are composed of these small building blocks Some

of the simplest life forms such as bacteria, are unicellular: they consist of a single cell In contrast, the body of the human or a maple tree is made of a

billions of cells In these complex multicellular organisms, life processes

depend on the coordinated functions of the components cells

Viruses are not considered organisms They can carry on life activities and reproduce only by using the metabolic machinery of the cells they

parasitize, and so are said to be on the borderline between living and nonliving things

2 Living organisms grow and develop

Some nonliving things appear to grow Crystals may form in a

supersaturated solution of the salt; as more of the salt comes out of the

solution, the crystal may enlarge However, this is not growth in the biological

sense Biologists defined as an increase in the amount of living substance in the organism Growth can result from an increase in the size if the individual

cells, the number of cells, or both Growth maybe uniform in the various parts

of an organism, or it may be greater in some parts than in others, causing the body proportions to change as growth occurs

3 Metabolism includes the chemical processes essential to growth, repair, and reproduction

In all living organism, chemical reactions and energy transformations take place that are essential to nutrition, growth and repair of cells, and

conversion of energy into usable forms The sum of all chemical activities of the organism is its metabolism Metabolic reactions occur continuously in every living organism, and they must be carefully regulated in maintain a

balanced internal state The tendency of organisms to maintain a relatively constant internal environment is termed homeostasis, and the mechanisms that accomplish the task are know as homeostatic mechanisms

4 Movement is a basic property of cells

Although not necessarily locomotion (moving from one place to

another), is another characteristic of living organisms The living materials within cells is in continuous motion, and organisms move as they interact with the environment

Most animals move very obviously; they wiggle, crawl, swim, run, or fly Locomotion may result from the slow oozing of the cell, from the beating

of tiny hair-like extension of the cell called cilia or longer structures know as flagella, or from the contraction of muscles A few animals, such as sponges, corals, and oysters, have free-swimming larval stages but do not move from place to place as adults Even these adults, described as sessile, remain firmly attached to some surface, they may have cilia or flagella These structures beat rhythmically, moving the surrounding water that brings food and other

necessities to the organism

5 Organism respond to stimuli

All forms of life respond to stimuli, physical or chemical changes in their internal or external environment Stimuli that evoke a respond in most organisms are changes in the color, intensity, or direction of light; changes in temperature, pressure or sound; and changes in the chemical composition of the surrounding soil, air or water In simple organisms, the entire organism may be sensitive to stimuli Certain single- celled organisms, for example, respond to bright light by retreating In complex animals such as polar bears or humans, certain cells of the body are highly specialized to respond to certain types of stimuli For example, cells in the retina of the eye respond to light

Although their responses may not be as obvious as those of animals,

plants do respond to light, gravity, water, tough, and other stimuli The streaming motion of the cytoplasm in plant cells may be speeded up or stopped by changes

in the amount of light Many plant responses are carried out by different rates of growth of various parts of the plant body A few plant, such as the Venus flytrap

of the Carolina swamps, are remarkably sensitive to tough and can catch inserts Their leaves are hinged along the midrib and they have a scent that attracts insects The present of an insect on the leaf, detected by trigger hairs of the leaf surface, stimulates the leaf to fold When the edges come together, the hairs interlock to prevent escape of the prey The leaf then secretes enzymes that kill and digest the insect The Venus flytrap is usually found in soil that is deficient

in nitrogen The plant obtains part of the nitrogen require for its growth from the insect prey it “eats”

6 Organisms reproduce

In simple organisms such as amoeba, reproduction may be asexual- that

is , without sex When an amoeba has grown to a certain size it reproduce by splitting it in half to form two new amoebas Before it divides, an amoeba make

a duplicate copy of its hereditary material (genes) and distributes one complete set to each new cell Except for size, each new amoeba is similar to the parent cell (The new amoeba may not be identical to each other or to the parent cell because mutations may occur)

In most plants and animals, sexual reproduction is carried out by the reproduction of specialized egg and sperm cells that fuse to form a fertilized egg The new organism develops from the fertilized egg Offspring produced by

sexual reproduction are the product of the interaction of various genes

contributed by both the mother and the father Such genetic variation provides raw material for the vital processes of evolution and adaptation

7 Populations evolve and become adapted to the environment

The ability of a population to evolve (change) and adapt to its

environment enables it to survive in a changing world Adaptation are traits that enhance an organism’s ability to survive in a particular environment They may

be structural, physiological, behavioral, or a combination of all three The long, flexible tongue of a frog is a adaptation for catching insects, and the thick fur coat of the polar bear is an adaptation for surviving frigid temperatures Every biologically successful organism is a complex collection of coordinated

adaptations produced through evolutionary processes

III ESSENTIAL CHARACTERISTICS OF LIFE

There are many characteristics processed by living organisms in

common By these characteristics we can distinguish living things from living things

non-1 Feeding or nutrition

Every organism must take in food from its surroundings The function of food id to provide energy for living process and to provide the raw materials necessary for growth Green plants possess chlorophyll and can make their own

food by photosynthesis This is a form of autotrophic nutrition Animals and

fungi cannot make their own food They have to obtain food from other

organisms, digesting the organic compounds by enzymes and absorbing the

products into the body This is called heterotrophic nutrition

There are many chemical processes, such as respiration, taking place inside the

cells of an organism These are collectively called metabolism Some of the by

products of metabolism are of no use to the organism and may even be harmful

if allowed to accumulate The removal of such waste substances from an

organism is called excretion In mammals, carbon dioxides is excreted by the lungs during breathing out or exhalation and nitrogenous wastes (mainly urea) are excreted by the kidney as the urine

Plants do not process excretory organs They usually get rid of metabolic

wastes by turning them into harmless substances which are stored within the body Leaf fall also eliminates metabolic wastes in some plants

4 Growth

Every organism gets bigger and more complex as it gets older Nonliving

things also grow, such as crystals, by the addition of new material to their external surface Living organisms, however, grow from within by the

formation of new living matter or protoplasm For this to take place, they must

obtain food by autotrophic or heterotrophic nutrition

5 Reproduction

The lifespan of organisms are limited They eventually die through aging,

diseases, predation or accidents However, they have the ability to perpetuate

their own species They produce offspring by sexual or asexual reproduction

The resulting offspring have similar characteristics as their parents

In asexual reproduction, a part of the parent becomes separated and develops into a new individual In sexual reproduction, two individuals of

opposite sexes are involved The male gamete (sperm) fuses with and fertilizes the female gamete (ovum) to form a zygote The zygote becomes an embryo

which later develops into a new individual

6 Irritability (or sensitivity)

Living organisms have the ability to detect changes in both the internal and external environments (we call these changes stimuli) and respond to them For example, the superficial blood vessels in the skin of a mammal dilate in

respond to a rise in body temperature in order to increase the rate of heat loss

If your eyes are exposed to bright light, the iris responds by diminishing the pupil diameter Green plants can also detect external stimuli such as light and water, but they respond more slowly than animals

7 Movement

Animals move from place to place (locomotion) to search for food and

escape from their enemies Plants on the other hand, can manufacture their own food by photosynthesis from raw materials obtained in one place, and most of them are anchored into the soil by roots Their movements are comparatively slow, being restricted to bending growth responses of the shoot and the root

B COMPREHENSION EXERCISES

I Decide the following statements are true or false

1 One of the functions of food is to provide energy for living process

2 Willows can make their own food from other organisms, and digest the

organic compounds

3 There are 2 kinds of reproduction

4 During respiration, plants require CO2 and give off O2

5 Respiration occurs in every cell in the body of the animals, but plants

6 The iris dilates is an example of adaptation of mammals in respond to the rise

of temperature

7 Viruses are organisms that can carry on life activities

8 The tendency of organisms to maintain a relatively constant internal

environment is termed homeostatic mechanisms

II Fill in each gap proper words / a word to make meaningful

statements

1 The sum of all the chemical activities of the organism is its

2 The tendency of organisms to maintain a constant internal environment is termed

3 A(n) is a physical or chemical change in the internal or external environment that causes a response in an organism

4 and flagella are used by some organisms for locomotion

5 A population must be able to to changes in its environment in order

to survive

6 An organism that cannot synthesize its own food from inorganic materials and must eat producers

7 The basic unit of life

8 Living things grow by increasing of cells

9 Metabolism can be described a the sum of all the that take place in the organism

10 is the tendency of organisms to maintain a constant internal

environment

11 In general, living things reproduce in one of two ways

12 The process by which living thing become adapted to their environment, or change, is called

III Choose the correct answer

1 Which of the following is not a characteristic of all living organisms?

a living things respond to stimuli

b living things exhibit movement and locomotion

c living things reproduce

d living things grow and develop

2 Biology is the:

a study of plants b study of animals

c study of life d study of inorganic and organic life

3 Which of the following life forms carry on cellular respiration?

a bacteria b fungi c plants d animals e all of the above

4 Fertilization is the:

a union of two sex cells to form a zygote

b transfer of pollen to the ovule

c transfer of pollen to the antheridium

d growth of the embryo into a new individual

5 The characteristic (s) common to all living things include (s)

a development b metabolism c adaptation d homeostasis

7 The function of homeostasis in a living organism is to:

a provide for unlimited growth

b allow unrestricted movement

c allow for adaptation to a harmful environment

d maintain a uniform or constant internal environment

8 An example of evolution is the appearance of giraffes with long necks The long neck gave these giraffes a selective advantage because it allowed them to:

a drink easier b see predators easier c reproduce easier

d have better homeostasis e eat the leaves at the top of the tree

9 Adaptation are traits that enhance an organism’s ability to survive in a

particular environment They may be:

a behavior b physiological c structural d All above are

correct

10 Reproduction that involves 2 different parents joining to form a new

individual Includes a combination of new traits

c asexual reproduction d reproduction

11 Organism that can use sunlight energy to synthesize complex food molecules are known as:

a heterotrphs b autotrops

12 The cell theory states that all living organisms:

a grow and develop b respond to stimuli

c are composed of basic unit called cells

d cam move from one place to another

13 An example of evolution is the appearance of giraffes with long necks The long neck gave them a selection advantage because it allows them to:

a drink easier b see predator easier

c reproduce easier d eat the leaves at the top of the tree

14 Organisms can reproduce by asexual reproduction and sexual reproduction

A benefit of sexual reproduction is that:

a more offspring can be produced

b the offspring are all identical to the parents

c the interaction of the genes brings about variation

d evolution will occur at a slower rate when you have 2 parents

* GRAMMAR NOTE: TO/ IN ORDER TO/ SO AS TO + V-INFINITIE

UNIT 2: BOTANY

A READING TEXTS

I AN INTRODUCTION TO PLANT BIOLOGY

- Plants are living organisms belonging to the kingdom Plantae They include

familiar organisms such as trees, flowers, herbs, bushes, grasses, vines, ferns, mosses, and green algae The scientific study of plants is known as botany

- Botany, sometimes referred to as plant science or plant biology, is the branch of biology that deals with the scientific study of plant life The word botany is referring to pastures, meadows, grass, fodder Botany is considered to be one of the oldest sciences

as it began with the effort of early humans to identify edible, poisonous and medicinal plants

When scientists first began grouping similar types of living things together, all organisms were identified as either plants or animals Botany covered all organisms not classified as animals As science has progressed, many organisms that were one included in the study of botany are no longer technically considered to be a part of the plant kingdom, such as fungi, lichens, bacteria, viruses and single-celled algae Botanists continue, however, to study these some of these life forms and so it is common to see organisms such as fungi, lichens certain bacteria and photosynthetic protists covered by botanical studies

II THE IMPORTANCE OF BOTANY

- The study of plants is of great importance to humans Plants generate the oxygen we breathe, are a major part of the food consumed by humans and animals, and are used to create fibers, fuels and medicines essential to our lives Plants absorb carbon dioxide, which is important in lowering greenhouse gasses, and are crucial to the water cycle

- Nearly all the food we eat comes (directly and indirectly) from plants like this American long grain rice.Virtually all foods eaten come from plants, either directly from staple foods and other fruit and vegetables, or indirectly through livestock or other animals, which rely on plants for their nutrition

-Fundamental life processes: Plants are convenient organisms in which fundamental life processes (like cell division and protein synthesis) can be studied, without the ethical dilemmas of studying animals or humans

-Medicine and materials: Many medicinal and recreational drugs, like tetrahydrocannabinol, caffeine, and nicotine come directly from the plant kingdom Others are simple derivatives of botanical natural products; for example, aspirin is based on the pain killer salicylic acid which originally came from the bark of willow trees

- Environmental changes: Plants can also help us understand changes in on our environment in many ways

 Understanding habitat destruction and species extinction is dependent on

an accurate and complete catalog of plant systematics and taxonomy

 Plant responses to ultraviolet radiation can help us monitor problems like ozone depletion

 Analyzing pollen deposited by plants thousands or millions of years ago can help scientists to reconstruct past climates and predict future ones, an essential part

of climate change research

 Recording and analyzing the timing of plant life cycles are important parts of phenology used in climate-change research

 Lichens, which are sensitive to atmospheric conditions, have been extensively used as pollution indicators

III THE DISCOVERY OF PHOTOSYNTHESIS

1 Bacteria to Plants

The first organisms to photosynthesize were bacteria Very recent studies reveal that the first bacteria to do so were the non-oxygen producing purple and green bacteria, followed by heliobacteria Later-developing bacteria produced oxygen in photosynthesis, as does the commonly known cyanobacteria which appeared even later, followed by algae and plants

2 Photosynthesis

6H2O + 6CO2 6H1206 + 6O2

This means that six molecules of water and six of carbon dioxide, in plants, with energy from sunlight, will produce one molecule of sugar and six of oxygen But this is a simple statement for a very complex process

In a typical terrestrial plant, leaves take in oxygen and carbon dioxide, while the roots supply water through the plants vascular system The leaves must protect

themselves from drying out and still be able to exchange gases, so they have special holes called stomata for gases to enter or be released They still do lose a lot of water, but it usually allows them to retain enough to not dry out

Photosynthesis takes place in chloroplasts, which are organelles, or parts of the plant’s cells The chloroplasts contain pigments in little stacks of structures called thylakoids There are many thylakoids in the chloroplast, arranged in pancake-like stacks called granum These are all surrounded by a liquid called stroma, all of which play a part in photosynthesis

Photosynthesis takes two different steps These steps are called light reactions and dark reactions In the light reaction phase, energy from the sun causes the chlorophyll to lose an electron It’s going to want to get that electron back though, so it takes it from the water This is when the oxygen is released as a waste product The electron that was originally lost from the chlorophyll goes through a series of proteins called the electron transport chain This process creates chemical energy called ATP and NADPH, which are used in the second step In the second step, the hydrogen left over from when the oxygen gets released from water is added to carbon dioxide with the energy created earlier to make sugar in a process called the Calvin Cycle It’s these sugars that everything else in the world needs to feed on, either directly or indirectly through eating the plants

Algae

Most algae are no longer classified within the Kingdom Plantae The algae comprise several different groups of organisms that produce energy through photosynthesis, each of which arose independently from separate non-photosynthetic ancestors Most conspicuous among the algae are the seaweeds, multicellular algae that may roughly resemble terrestrial plants, but are classified among the green, red, and brown algae Each of these algal groups also includes various microscopic and single-celled organisms

Fungi

The classification of fungi has been controversial until quite recently in the history of biology Linnaeus' original classification placed the fungi within the Plantae, since they were unquestionably not animalian; this being the only other alternative With later developments in microbiology, in the 19th century Ernst Haeckel felt that a

third kingdom was required to classify newly discovered micro-organisms The introduction of the new kingdom Protista as an alternative to Animalia, led to uncertainty as to whether fungi truly were best placed in the Plantae or whether they ought to be reclassified as protists

Fossils :

Plant fossils include roots, wood, leaves, seeds, fruit, pollen, spores, phytoliths, and amber (the fossilized resin produced by some plants) Fossil land plants are recorded in terrestrial, lacustrine, fluvial and nearshore marine sediments Pollen, spores and algae (dinoflagellates and acritarchs) are used for dating sedimentary rock sequences The remains of fossil plants are not as common as fossil animals, although plant fossils are locally abundant in many regions worldwide

The earliest fossils clearly assignable to Kingdom Plantae are fossil green algae from the Cambrian These fossils resemble calcified multicellular members of the Dasycladales Earlier Precambrian fossils are known which resemble single-cell green algae, but definitive identity with that group of algae is uncertain

FACTORS AFFECTING GROWTH

The genotype of a plant affects its growth For example, selected varieties of wheat grow rapidly, maturing within 110 days, whereas others, in the same environmental conditions, grow more slowly and mature within 155 days.[23]

Growth is also determined by environmental factors, such as temperature, available water, available light, and available nutrients in the soil Any change in the availability of these external conditions will be reflected in the plants growth

Biotic factors are also capable of affecting plant growth Plants compete with other plants for space, water, light and nutrients Plants can be so crowded that no single individual produces normal growth, causing etiolation and chlorosis Optimal plant growth can be hampered by grazing animals, suboptimal soil composition, lack

of mycorrhizal fungi, and attacks by insects or plant diseases, including those caused

by bacteria, fungi, viruses, and nematodes.[23]

Simple plants like algae may have short life spans as individuals, but their populations are commonly seasonal Other plants may be organized according to their seasonal growth pattern: annual plants live and reproduce within one growing season, biennial plants live for two growing seasons and usually reproduce in second year, and

perennial plants live for many growing seasons and continue to reproduce once they are mature These designations often depend on climate and other environmental factors; plants that are annual in alpine or temperate regions can be biennial or perennial in warmer climates Among the vascular plants, perennials include both evergreens that keep their leaves the entire year, and deciduous plants which lose their leaves for some part of it In temperate and boreal climates, they generally lose their leaves during the winter; many tropical plants lose their leaves during the dry season

B COMPREHENSION EXERCISES

I Decide the following statements are true or false

1 Seaweeds are a kind of algae

2 Seaweeds are terrestrial plants

3 All of the algae are single-celled organisms

4 According to Linnaeus, fungi belongs to plantae

5 The earliest fossils clearly assignable to Kingdom Plantae are fossil green algae

6 Photosynthesis takes many steps: light reaction, dark reaction

7 The first organisms to photosynthesize were fungi

8 The chloroplasts contain thylakoids

II Answer the following questions:

1 What is botany?

2 What are the roles of plants in our life?

3 How do plants help us understand the changes in our environment?

4 How many groups of organisms?

III Fill in the blank one word to complete each sentence

1 …… Is the branch of biology that deals with scientific study of plant life

2 The first organisms to photosynthesize were………

3 In a typical terrestrial plant, O2 and CO2 are taken in the palnt by ……… while thw water is supplied by ……… through the plants vascular system

4 ………… are holes that gases enter or be released

5 Photosynthesis takes place in……

C LANGUAGE FOCUS:

S + USE S.TH + TO V-INFINITIVE = BE USED TO + V-infinitive

Use given words to make full sentences

1 Greenplants/ use/ chloroplasts/ photosynthesize

2 Animals/ use/ kidney/ excrete

3 Greenplants/ use/ roots/ absorb/ water/ land

4 Human beings/ use/ plants/ make/ food

5 They/ use/ fresh flowers/ decorate/ room

1 All animals are eukaryotes: sinh vật nhân chuẩn

All living organisms can be sorted into one of two groups depending on the basic structure of their cells These two groups are called the prokaryotes (nhân sơ) and the eukaryotes

Prokaryotes and eukaryotes differ from one another in many fundamental ways but the differences are difficult to see Cells are tiny and you must use a microscope to view their internal structure But once magnified, the differences between prokaryotes and eukaryotes becomes more apparent The internal structure

of a prokaryote cell is less complex than that of a eukaryote Prokaryotes have no nucleus, eukaryotes have a nucleus In eukaryotes, the nucleus holds the cell's genetic material within a membrane In prokaryotes, genetic material is located in a central region of the cell and is called a nucleoid, it is not enclosed in a membrane

So all animals are eukaryotes That the reverse is not true—not all eukaryotes are animals Plants, fungi, and protists—in addition to animals—are eukaryotes

2 All animals are heterotrophs

All living things need carbon to support the basic processes of life such as growth, development, and reproduction There are two ways an organism can get the carbon they need:

 Assimilate carbon from their environment in the form of carbon dioxide (from the atmosphere) or inorganic compounds They can ingest other organisms and thus obtain carbon from the organic materials that make up the other organism The term autotroph describes such organisms

 Obtain the carbon they need by getting it from other living organisms that are made up of carbon-containing organic molecules The term heterotroph describes this type of organism, one that uses organic materials as a source of energy for growth and development

3 Animals are multicellular Most animals (with the exception of sponges) have bodies that are differentiated into tissues

Animals' bodies are made up of multiple cells In most animals, those cells are organized into different tissues that perform different functions During the development of an animal, cells differentiate so they can perform specific functions