biology chapter 2

Chapter 2

CELL STRUCTURE AND

CELL ORGANISATION

2.1 CELL STRUCTURE AND FUNCTION

ii ) component of a cell

At the end of the lesson, student should be able to:

Define the term of organellesIdentify the component of

organelles in an animal cell and plant cell

state the functions of the cellular components in an animal cell

state the functions of the cellular components in a plant cell

COMPONENTS OF A CELLCellular component of a cell as seen via

electron microscope are:-a) Plasma membrane and cell wallb) Cytoplasmc) Organelles cell surrounded by plasma membrane

contain cytoplasm ~~ jelly like substancePlant cell ~~ addition of cell wallCytoplasm contain many ORGANELLES

Specialised structure which surrounded by its own membrane and perform specific function

Organelles in animal ~~ 1)nucleus, 2)rough and 3)smooth endoplasmic reticulum, 4)mitochondria, 5)Golgi apparatus, 6)lysosomes,7) ribosome,8) centrioles and 9)vacuoles

Plant cell have chloroplast in addition but did not have centrioles

Function of cellular component

STRUCTURE

Organelles Non-

organelles

Mitochondria

Lysosome

Ribosome

Chloroplast

Centrioles

Vacuoles

Golgi apparatus

Nucleus

ER

Plasma membrane

Cytoplasm

Cell wall

ORGANELLES

NUCLEUS

STRUCTURESpherical with double

membrane contain nucleolus, chromosome and nuclear membrane

FUNCTION Control and regulate

all activities on cellContain hereditary

factor (gene)~responsible for trait

RIBOSOME

STRUCTURESmall particle consist

of RNA Exist freely in

cytoplasm or on the surface of rough ER

FUNCTIONSynthesis of

protein

Rough and smooth ERSTRUCTURE

System of membrane enclosed tubules closely packed together and continuous with nuclear membrane

Rough ER has ribosome while smooth ER did not have

FUNCTION Transport system for protein and

lipid within the cell Rough ER transport protein

synthesis by ribosome to other part of the cell

Smooth ER stimulate the synthesis of lipid and cholesterol and transport within cell

MITOCHONDRIASTRUCTURE

Rod-shape with a double membrane

Outer membrane is smooth and regular while inner membrane is folded to form cristae

FUNCTIONKnown as the ‘power-

house’ of the cellReleases energy as it the

site for aerobic respiration

GOLGI APPARATUSSTRUCTURE

Vacuolar region surrounded by a complex meshwork of vesicles budding off at its end

FUNCTION Receive protein and lipid

from ER and modify them to form secretion ~enzyme /hormone

Pack the secretion formed into vesicle and transport to plasma membrane

Control secretory activity Form lysosome

LYSOSOMESSTRUCTURE

Membrane bound vesicle found in animal

FUNCTIONContain enzyme which

control breakdown of protein and lipid

Contain enzyme that digest aged or defective cell component

26th January 2010

CHLOROPLASTSTRUCTURE

Disc-shape organelles with double membrane

Consist arrangement of grana within stroma

Each granum contain chlorophyll

FUNCTIONCarry out

photosynthesis

CHLOROPLAST

CENTRIOLES

STRUCTUREConsist of two cylindrical

body structure arranged at right angles to one another

Only in animal cell

FUNCTIONFormation of spindle

fiber during cell division

VACUOLE

STRUCTURECavities filled with cell

sap surrounded by a semi-permeable membrane called tonoplast

FUNCTIONContain water, sugar

and dissolve materialsMaintain turgidity of

cell in plant

NON-ORGANELLES

PLASMA MEMBRANE

STRUCTUREThin, semi-

permeable membrane

FUNCTIONControl the

movement of substance in and out of the cell

CELL WALL

STRUCTUREThick layer outside the

plasma membraneMade up of cellulose

and fully permeable

FUNCTIONMaintain the shape

of plant cellProvide support

CYTOPLASM

STRUCTUREJelly-like

substance contain water and mineral salt

Contain organelles

FUNCTIONMedium for

metabolic reaction

Cytoplasm

Lets review……

Can you recognize the organelles involve in this picture?

Complete the table below

STRUCTURE

Organelles Non-

organelles __________

structure :Function :

__________structure :Function :


__________structure :Functon :








Homework












Lets make a revision

List all the organelles found in the animal and plant cell

Lets watch this video and make a video summarization

Homework

LETS DO AN ACTIVITY Divide yourself into 6 group

Each group will be prepared by modeling clay and manila card.

Each group’s representative will vote for cell

In 15 minutes, by using your creativity, build a model based on the cell and their organelles

Need to label each structure and state their function

Comparison Between The Structure Of An Animal Cell

And Plant CellSIMILARITIES

Both have membrane, cytoplasm, nucleus, mitochondria, Golgi apparatus and ER

DIFFERENCES

ANIMAL CELL Criteria PLANT CELL

smaller Size larger

No fixed shape Shape Have fixed shape

No regular pattern Pattern Arrange in regular pattern

Do not have vacuole Vacuole Large central vacuole

absent chloroplast

Present and contain chlorophyll

Do not have cell wall Cell wall Has cellulose cell wall

Glycogen granules Granules Starch granules

Relationship between the density of organelles and the function of cell

No. of specific organelles depend on ~~type of cell and its function

Active cell ~~↑ mitochondria to provide energy Eg : SPERM CELL ~need to swim toward ovum

: FLIGHT MUSCLE CELL ~to move their wing during flight

: CELL IN MERISTEMS (plant shoot and root) ~active cell division to produce new cell

↑ chloroplast to carry out photosynthesis ~MESOPHYLL CELL ~GUARD CELL

2.2 CELL ORGANIZATION

Chapter 2 : Cell structure and cell organization

We, as multicellular organism can feed, respire, excrete, move, respond to stimuli, reproduce and grow.

Unicellular organism is organism with just one single cell. So how come this organism perform all the living process????

By the end of the lesson, student should be able to :-

Understand living process in unicellular organism

the movement in unicellular organism

the reproduction in unicellular organism the feeding in unicellular

organism the exchange of materials in unicellular

organism

CELL ORGANIZATION

ORGANISMS

UNICELLULAR ORGANISM

Single cell organism

MULTICELLULAR ORGANISM

larger organism with more than one cell

UNICELLULAR ORGANISM

Simple organism consist of one cell each

Each cell or organism is complete unit of life ~able to carry out all living processes

Eg: ____________

Living processes of unicellular organism

~~~ Amoeba sp free living in fresh water Enclose in plasma membrane constantly change shape

depend on stimuliAlso called protozoa

Let’s do an activity Divide yourself into 4 group

Each group’s representative will draw lots for the topic and take manila card and marker pen

Within 15 minutes, in group, discuss the topic and draw the processes occur

After that, each group will

present their work

Movement of Amoeba sp.

Move by extending temporary pseusopodia or ‘false foot’ that anchor the ground

The rest of cytoplasm flow slowly into this extension, hence move the org. along

Reproduction of Amoeba sp.

Once grown to certain size, the nucleus divided to form 2 daughter cell

Cytoplasm divided and 2 daughter cell form ~~ binary fission by asexually

When envi. not conducive, divided by spore formation

Feeding of Amoeba sp.

Engulf food via phagocytosis

Holozoic org. feed on microb

It move around food particle, and take it into cytoplasm ~~food vacuole

Hydrolytic enzyme (lysozyme) are added and nutrient absorb into cytoplasm

Material exchange of Amoeba sp.

Exchange of gases, nutrient and waste occur via plasma membrane ~~diffusion

Water diffuse into cell ~osmosis and fill contractile vacuole

When fill to max, it contract to expel its content

THE ENDThanks for your cooperation

MULTICELLULAR ORGANISMOrganism - more than one cellLarger org. ~Need many different type

of cell to carry out life processAchieve via cell specialization and cell

organisation

2.2 CELL ORGANISATION


Each type of cell has diff. size, shape and structureEach cell not capable to perform all life process

~~ CELL SPECIALISATION to perform different function Achieve via DIFFERENTIATION ~cell begin CHANGE

shape and structure during grow Each type of cell perform only one specific function ~

DIVISION OF LABOUR

Cell organisation in multicellular organism

CELL

TISSUES

ORGANS

SYSTEMS

MULTICELLULAR ORGANISM

Lets do it! Divide yourself into 5 group

Each group’s representative will vote for title

Each group will be prepared by manila card and marker pen.

In 20 minutes, make a mind mapping about our title and present to the class

CELL ORGANISATION IN ANIMAL

TISSUES

EPITHELIAL TISSUES

MUSCLE TISSUESCONNECTIVE

TISSUES

NERVE TISSUES

Regulating the internal environment

At the end of the lesson, student should be able to :-

State the meaning of internal environment, external environment and interstitial fluid

Identify factors affecting the internal environment

Explain the necessity to maintain optimal internal environment

Describe the involvement of various systems in maintaining optimal internal environment.


Lets get familiar with the term first

EXTERNAL ENVIRONMENT – condition outside org. ~surrounding

INTERNAL ENVIRONMENT – condition inside org. , cell of body live within ~(own metabolism)

INTERSTITIAL FLUID – space between the cell & constant bath the cell ~exchange substance with blood plasma

Maintaining optimal internal environment

External envi influence ~internal envi ~extracellular fluid

~~need to maintain for cell to function optimally ~keep internal envi. constant

PHYSICAL FACTORBlood P

Osmotic PT

CHEMICAL FACTORSalt

pH valueSugar content

FACTORS

HOMEOSTASIS

Process regulate P&C factors in internal envi so that it always constant

If any P&C factor deviate from constant value( OR ), it trigger homeostasis mechanism to bring it back to normal ~~~NEGATIVE FEEDBACK MECHANISM

IMPORTANT OF HOMEOSTASIS :-a) Change in pH or T, effect enzyme

activityb) Change in osmotic P, gain or loss

waterc) Change in glucose level, relate on

energy

Involvement of various system in maintain optimal internal envi.

Various system interact to regulate and maintain internal envi.

Eg : (body T) by integumentary sys., nervous sys, muscular sys and endocrine sys

NEGATIVE FEEDBACK MECHANISM

Normal body T

Receptor at skin detect

hypothalamus

Blood vessel dilate

Normal body T

Receptor at skin detect

hypothalamus

Blood vessel shrink

YOUR HOMEWORK

Please make a negative feedback mechanism on others factors that you have learn

THANKS YOU

For your attention, I would like to say…

biology chapter 2

Education