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 AMOEBA SP.Done By : Janice, Nabilah, Jasmine, Jazelle, Sharon,

 Wei Yun, Theva

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Adverse Stimuli(e.g.acidic

water or bright light)

Flow Chart

Extend pseudopodium

Flow of cytoplasm into

pseudopodia

Locomotion takes

place

Anchoring the tips on the ground

Amoeba movement isknown as amoeboid

movement.

MOVEMENT

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MOVEMENTSol-Gel Theory :

The interchange of plasmasol to plasmagel is

known as Sol-Gel theory and is responsible for 

amoeba movement.

The cytoplasm of amoeba consists of a central

fluid plasmasol(endoplasm) surrounded by a

more viscous plasmagel(ectoplasm).

The amoeba propels itself when the endoplasm

flows towards the front of the cell, forming

pseudopodium and is converted into plasmagel.

At the same time, the plasmagel at the rear of 

the cell is converted into plasmasol and streams

forward, maintaining continuous movement.

Movement takes place only when the 

cytoplasm is in fluid state.

(fluid state)

(solid or gel like state)

cytoplasm

(i.e.false feet)

(plasmasol)

(plasmagel)

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Plasma membrane

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GROWTH

Nucleus controls the growth

Grows by synthesizing new cytoplasm

Feed and grow until they are big enough to split off

Some Amoeba sp. can grow up to 5mm long. This is exceptionally

large for a unicellular organism. They can reach this size by having

multiple nuclei within a single cell.

Amoeba Dubia

Grows up to a micrometer and

are visible to naked eyes

Amoeba Proteus

Grows up to 700-800

micrometers in length

Two type of amoebas: amoeba proteus and amoeba dubia

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1) First, the amoeba

will stop moving and

rounds off.

2) Second, the

nucleus in the

amoeba begins to

divide.

3) Then, the nucleus

divided and thecytoplasm starts to

constrict.

4) The constriction

continues to divide

the cytoplasm of the

amoeba.

5) The daughter of 

the amoeba isseparated.

Note : Amoeba reproduces by Binary Fission. But, when

the environment is not conducive(e.g food is scarce and

condition is dry) to reproductions, spores will be formed.

REPRODUCTION

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The amoebaheads toward

the unsuspecting paramecium.

It begins tospread out it's

 body to catch its prey.

The amoebakeeps changingits shape until itcan enclose its

 prey.

The parameciumwill soon

completely insidethe amoeba!

The amoeba willabsorb its lunch

directly inside itscell walls.

Amoeba eating a Paramecium