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c Complex protein ring structures anchored in the bacterial cell membranes form a motor unit that rotates the flagellum and propels the cell, Inside of cell The flagellum is rotated

ĐẠI CƯƠNG TẾ BẢO

Các giới sinh vật

Eukarya share a EUKARYA

bacteria

There are multiple protist

different protist ancestors

Protists

Time

Đồi tượng, nhiệm vụ, lược sử và

phát triên của sinh học tê bào

hương pháp nghiên cứu

Hoc thuyét té bao

¢ Thanh phan hoa hoc cla té bao (life science) Thanh phân nguyên tố

Các liên két hoá học

Thành phân hợp chất

Vô cơ, hữu cơ

—-

Electrical sparks Qt — WA

simulating light- x cH ning provide ei 4 energy for syn- NEI eo

3 Hoe thesis of new “Atm heric”

compounds compartment

A condenser cools the

“atmospheric” gases in )—~ Cold

a “rain” containing new water

The compounds react in

purines, pyrimidines, and amino acids

vvater, eventually forming im Ly

Ệ- scale is logarithmic Each unit is =|

times bigger than the previous unit

llnmn iInm Wom 100nm lụm Wem 10pm = lmm lem 0.1m Im 10m 100m km

< Unaided eve >

California redwood

Most cell diameters are in

the range of 1-100 um

(a) Small icosahedral viruses

om Viruses Proteins involved in DNA, RNA,

Possible gene therapy approaches

(a) Prokaryotic cell

Nucleoid

Uipoprolenn | I

~~

vách tế bao Gram 4m

Photo Researchers, Inc.jOmikronJ5cience SnUIFCE

existence of several protective structures external to the plas- Other prokaryotes have internal membrane {

ma membrane remain attached to the plasma membrane These |

`

| (0) Hairlike pili help this bacterium

| adhere to other cells,

4.6 Prokaryotic Projections Surface projections such as bacterial

flagella (a) and pili (b) contribute to the movement, adhesion, and

complexity of prokaryotic cells (c) Complex protein ring structures

anchored in the bacterial cell membranes form a motor unit that

rotates the flagellum and propels the cell,

Inside of cell

The flagellum is rotated by a complex protein

“motor” secured in the plasma membrane,

> The mitochondrion is a power plant and industrial park,

where energy stored in the bonds of carbohydrates is converted to a form more useful to the cell (ATP) and

certain essential biochemical conversions of amino acids

and fatty acids occur

Té bao nhan chuan

nuclear pore

chromatin (DNA) nucleus

nucleolus nuclear envelope

Everything between the cell wall and nucleus is

called the cytoplasm The ground substance

in which all the organelles are suspended is

7] Nuctleolus

A cytoskeleton composed of

micronubauhs and microfilamerr:

= = —_ supports the coll and i= involwed in

most cellular DONA which

with associated proteins

Inside of cell

oll from its onwironmert and

| regulates traffic of materials irto and

©+# Of the coll

tures unique to plant ceils Include the ceil wall and the chioroptiasts Animal

cells comtain Centrick€s, whith are not found in plant cells

chemically modfikd in the

smooth ondoplasmic reticulum

Poroxisomes brook O75 um (A coll wall suppor: ) 0.75 um

Matrix Intermembrane space

4.21 The Cytoskeleton Three highly

visible and important structural compo-

nents of the cytoskeleton are shown here

in detail These structures maintain and

reinforce cell shape and contribute to cell

Fibrous subunit Tubulin B-Iubulin o-Tubulin

dimer monomer monomer

Leen

10 um

THE PLANT eH)

upper epidermis midrib

shoot apical meristem

in lover epidermis

The young flowering plant shown on the /eft is constry from three main types of organs: leaves, stems, and 19 Each plant organ in turn is made from three tissue sys)

ground, dermal, and vascular

All three tissue systems derive ultimately from thee: proliferative activity of the shoot or root apical meriste and each contains a relatively small number of special cell types These three common tissue systems, and th cells that comprise them, are described in this panel,

b cá tến

1

# GROUND TISSUE (C—): This packing and supportive

THE THREE TISSUE SYSTEMS

Cell division, growth, and differentiation give rise to tissue systems with specialized functions

‘DERMAL TISSUE (IB): This is the plant's protective

outer covering in contact with the environment |t | facilitates water and ion uptake in roots and regulates gas exchange in leaves and stems a |

GASCULAR TISSUE: Together the phloem (=) ang]

the xylem (MiB) form a continuous vascular system< throughout the plant This tissue conducts water and

solutes between organs and also provides

mechanical support

tissue accounts for much of the bulk of the young plant It also functions in food manufacture and storage :

oes

GROUND TISSUE

~

The ground tissue system contains a

‘three main cell types called parenchyma, ˆ hie collenchyma, and sclerenchyma ey)

A Parenchyma Cells are found in all tissue systems They are living

cells, generally capable of further division, and have a thin

primary cell wall These cells have a variety of functions The

apical and Jateral meristematic cells of shoots and roots provide

the new cells required for growth Food production and storage

occur in the photosynthetic cells of the leaf and stem (called

mesophyll cells); storage parenchyma cells form the bulk of most fruits

and vegetables Because of their proliferative capacity, parenchyma

cells also serve as stem cells for wound healing and regeneration

50 um

A transfer cell, a specialized form of the parenchyma cell, is readily identified by elaborate ingrowths of

the primary cell wall The increase

in the area of the plasma membrane beneath these walls facilitates the rapid transport of solutes to and from cells of the vascular system

Collenchyma are living cells similar to parenchyma cells

except that they have much thicker cell walls and are usually

elongated and packed into long

ropelike fibers They are capable

of stretching and provide

mechanical support in the ground tissue system of the elongating

regions of the plant Collenchyma cells are especially common in subepidermal regions of stems

typical locations of Supporting groups

of cells in a stem sclerenchyma fibers

vascular bundle

collenchyma

supporting functions However, they —

are usually dead cells with thick, lignified secondary cell walls that

prevent them from stretching as the plant grows Two common types are — fibers, which often form long bundles,

and sclereids, which are shorter branct

cells found in seed coats and fruit.

outer surface by a special

1 outer waxy layer The cells

Stomata are openings in the epidermis,

mainly on the lower surface of the leaf, that

Hairs (or trichomes) are Ssovencases derived from epidermai cells They existina variery

of forms and are commoniy found in all plant parts Hairs function in crotection

absorption, ana secretion: for exampbie,

g : epidermis hair -SO um

of the pore Stomata are distributed ina distinct species-specific pattern within each epidermis

Vascular bundles

Roots usually have a single vascuiar bundle, Dut stems have several bundles These are arranged with

strict rAdial symmetry in dicots but

they are more trregularly dispersed

in monocots

sheath of scierencnyvyma phicem xyiem parenchyma

and the xyiem together forma

ascular system throughout the

5ung plants they are usually

“with a variety of other cell types

‘bundles Both phicem and

sieve = plate ZeES

complex tissues Their conducting elements

ted with parenchyma cells that maintain and

materials with the elements Also, groups of

na and sclerenchyma ceils provide mechanical

plasma membrane

is involved in the transport of organic solutes in the ptant

in conducting cells (elements) are aligned to form tubes

jeve tubes The sieve-tube eiements at maturity are living

nterconnected by perforations in their end walis formed

niarged and modified piasmodesmata (sieve plates) These

‘etain their plasma membrane but they have lost their nuctei

such of their cytoplasm: they therefore rely on associated

Sbanion ceils for their maintenance These comoanion cells

the additional function of actively transporting soiubie food

les into and out of sieve-tube elements through porous sieve

sieve-tube element

in cross-section

young, single-celled hairs in the

epidermis of the cotton seed When

these grow, the weils wil be secondarily thickened with ceiluicose

to form cotton fibers

CHỊ

eciceammis —R

a muiticellutlar secretory hair from have an imrtorcant function

Singiecs.:2eda root hairs

3 geranium teaf in weiter =-—c ion uptake

<ylem

Xylem carries water and dissolved ions

in the pliant The main conducting ceils are the vessel elements snown here,

which are dead cells at maturity that lack

a plasma membrane The ceit well has

been secondarily thickened and heavily lignified As shown below its end wall is largely removed enabling very iong, continuous tubes to

be formed

large mature vessel eiement

The vessel elemenzs are ciosely

associated with xy!em parenchyn

cells, which activeiy transport

selected solutes into and out of th elements across their plasms

membrane

xylem parenchyma ce''s vessel element

SEELASRES

There are over 200

types of cells in the

human body These

ere assembied into a

= f f Absorptive cells Have nmumerous hairlike© Ciliated cells Have cilia on Secretory cells are fo

aS — = microvilli projemiing from tnerr free surface their free surface that most epithelial layer PMSSUSsAS to imcrease the ares for absorption beat in synchrony to specializecd cells secr

_= larmima È > E>

Most tissues contain = Adjacent epithelial celis are Dound :

a mixture of cell = togemer Dy junctions tnat Give the

types sheei mechanical strength and aliso

= make it impermeable to smali

= molecuies The sheet rests one

== E n a re a ed ew re sẽ ea ad oS Se Se tT SS SS > eee

CONNEC Hy] aa Sore

The spaces between organs anc tissues = Bone is made by cells called osteoblasts These = :

In the body are Tilled with connective secrete an extracellular matrix in which crystals Caicium salt

of tough protein fibers embedaced ina

polysaccharide gael This extracellutar

- matrix is secreted mainly by fibroblests

extracellular 1am

“twvo main types of extreceliular protein fHiper are collagen : 5 = = elestin ~~ esteoblasts linked

pate ả togeter by cell extraceliutar

ee processes matrix

cells in the body, are responsible

for the production and storage of fat The nucieus and cytoplasm are squeezed by ea large lipid dropiet

to a muscle cell)