Notes CHAPTER 2.doc

7/27/2019 Notes CHAPTER 2.doc

1/13

Science Module Form 1 Chapter 2

Prepared By : Abiana Bt. Jaafar(GCSC) 1 e-mail : a b ia n a jaa f a r @ y a ho o .c om

CHAPTER 2 : CELL AS THE BASIC UNIT OFLIFE

Parts of microscope :

An instrument that magnifies minuteobjects so they can be seen easily.It is one of the most important tools ofscience.Physicians and biologists usemicroscopes to examine bacteria andblood cells.

EyepieceMagnify the specimen by 10x

Rough focus knob

Change the position of theobjective lens when focusing

with low-powered objective

lens.

Fine focus knob

Change the position of theobjective lens slightly for fin

focusing. Used with high-

powered objective lens.

Objective lens Magnify the

size of a specimen by 4x,

10x or 40x.

Stage

Place the glass slide.

Clip

Hold the slide on the stage.

Diaphragm

Control the amount of light

entering objective lens.

There are four basic kinds of microscopes :

Optical or light microscopeElectron microscopeScanning probe microscopeIon microscope

Mirror

Reflects light up through anopening un the stage to

illuminate the specimen.

Base

Stabilize the microscope.
mailto:[email protected]:[email protected]


2/13

Chloroplast

VacuoleCell wall

Cell membrane

Nucleus Cytoplasm

Structure ofcell

Function

Nucleus Control all activities of the cell

Vacuoles

Stores salt and sugar solutions, hold waste

substances

ChromosomesDetermines how an organism behaves (geneticinformation)

Cytoplasm A place where all chemical reactions take place

Cell membraneControl the movement of substances into or out ofthe cell

Cell wall Support and gives the cell a regular shape

ChloroplastsA place where plants make food by photosynthesis.Contain chlorophyll which is used to trap sunlight for

photosynthesis.


3/13

}Cytoplasm

Nucleus Protoplasm

Cell membrane

Structure of the cell Function

Nucleus Controls all the activities of the cell

Cytoplasm A place where all chemical reactiontake place.Stores dissolves material

Cell membrane Controls the movement of material inand out of the cell


4/13

Co mp aring Animal Cel l an d Plan t Cel l

Similarities

Both have nu cle u s, c y t op las m and c e l lm e m br a n e.

Differences between plant cells and animal cells

Plant cell Animal cellRegular shape shape Irregular shape

With chloroplasts chloroplasts Without chloroplasts

With a cell wall(cellulose)

cell wall Without cell wall

Large vacuoles vacuolesHas no vacuoleexcept in unicellular


5/13

Review 1 : Animal Cel l a nd Plant Cel l

1. What is the basic unit of living things?

2. What makes up the protoplasm of a cell?

3. What can be found in plant cells but not in animal cells?

4. State the substances that builds up the cell wall of plants cells.

5. Draw an animal cell and plant cell.

Animal cell Plant cell


6/13

UNICE LL U L A R A N D MULTICELLULARO R G A N I S M S

Made up ofone cell only.

Uni means one.

Carry out life processesinside the cell.

Absorbs nutrients, expelwastes and exchangegas with their environment.

A simple organism Mostly are aquaticliving things (inponds, drains andthe sea).

Do not havecirculatory system.

Also known asmicroorganism

(microbe)

Examples :Paramecium, Amoeba,yeast, Pleurococcus,Chlamydomonas.

Asexual reproduction(Fission)


7/13

Made up ofmany cell.

Multi means many.

Examples :Human beings, birds, fishHydra, Spirogyra, moss,

earthworm, Mucor.

More complex thanunicellular organism

Life process are more

complex. Various types ofcell work together toperform a specific task


8/13

Euglena Paramecium Spirogyra ChlamydomonasHydra Mosquito Amoeba Moss

Scorpion Cockroach

Review 2 : Unicellular Cel l a nd Multicellula rCel l

1. What is unicellular organism?

2. What is multicellular organism?

3. Give two examples of unicellular organism.(a)(b)

4. Give two example of multicellular organism.(a)

(b)

5. Why is human being classified as multicellular organism?

6. Identify unicellular organisms and multicellular organisms given below.

Unicellula rOrganisms Multiicellula rOrgani sms


9/13

7. Name the organism below.

(a) (b) (c)

(d) (e) (f)


10/13

Prepared By : Abiana Bt. Jaafar(GCSC) 10 e-mail : a b ia n a jaa f a r @ y a ho o .c om

OR G AN IS AT I O N O F CE L L IN T HE HUM AN B O DY

Cell organization is the grouping of simple cell into more complex

structures.

CELL TISSUE ORGAN SYSTEM ORGANISM

Basicunit of

life

The smalleststructurescapable ofbasic lifeprocesses

ORGANISM

All system in the bodyfunction in a coordinatedmanner to form amulticellular organism.

Examples :

CELL Groups of organs form organ systemsEach organ system carries out a majoractivity in the body.Examples :

Epithelium cellRed blood cell

White blood cell

- Reproductive system- Blood circulatory system

- Digestive system

Cardiac muscle cellBone cell Nerve

cell Reproductivecell

SY-STEM

- Excretory system- Respiratory system- Muscular system

A group of similar cells that worktogether to perform a particular function.

TISSUE ORGAN

Four main types :- Epithelial tissue - Muscle tissue- Connective tissue - Nervous tissue

An organ consistof two or morkinds of tissue

joined into onstructure that haa certain task.Examples :- The heart

- The kidney- The lungs- The stomach- The liver - The brain
mailto:[email protected]:[email protected]


11/13

Type of humancell

Structure Respective function

Red blood cellTransports vital food and oxygen to all parts of thebody.

Nerve cellCarries messages in the form of electrical impulsesaround the body.

White blood cell Protects the body from damage by invaders

Human spermcell

Takes part in fertilisation to produce young ones.

Bone cell Form bones to support the body and protect organs.

Human egg cell If the egg is fertilised it will develop into an embryo.

Epithelial cell It protects the internal and external parts of the body.

Muscle cell Contracts and relaxes to move parts of the body.


12/13

The L y m ph a tic SystemBodys defencesagainst infection

The R e produ c tiv eS y s t e m

Forreproduction

The Sk ele t alSystemProtect internal organ.Provides body support

The N e r v ous SystemDetect stimuli andresponds to them.

The Blood Ci rculatoryS y s t e m

Supplies the cells ofthe body with thefood.Transport wasteproduct.

VARIOUSSYSYEM IN

THE HUMANBODY

The E ndo c rine SystemProduces, stores andsecretes chemicalsubstances known as

hormones.

The R es pir a t o r y SystemSupplies oxygen andaids removing of carbon dioxide

The Mu sc ula r SystemEnables body

movement.

The Ex c r e t o r y SystemRemoves wasteproducts from body.

The Dig es tiv e SystemProcesses food(ingestion, digestion,absorption).


13/13

Science Module Form 1 Chapter 2

Review 3 : O rg a n isation ofC el l

1. State the following structures as cell, tissue, organ or system.

(a) Sperm -

(b) Stomach -(c) Ovum -(d) Brain -(e) Digestive - (f)eardrum -

2. Complete the cell organization below.

Organism

3. State the name of each organ shown below and the system it belongs to .

(a) (b)

Organ :System :

Organ :System :

(c) (d)

Organ :System :

Organ :System :

Documents

Notes CHAPTER 2.doc