STRUCTURE OF CELL

CELL SHAPE

There is two type of cell one can change its shape and another having fixed shape.

Example of cell which can change its shape is:- Amoeba , white blood cells or leukocytes.

• Leukocytes have generally spherical in shape whiles in circulating with blood but in other condition it produce pseudopodia .
• most of the cells of plant and animals have fixed shape.

THE SHAPE OF CELL DEPENDS UPON:-

• In unicellular:- The shape of the cell is maintained by tough plasma membrane and exoskeleton.
• In multicellular:- The shape of the cell is depends mainly on its function and partially on its condition like surface tension, viscosity of protoplasm , rigidity of the cell membrane, 

CELL SIZE

• The range of the cell size is about( 0.2-5.0) micro meter to 18 cm.
•  The smallest cell is the Mycoplasma which is about 0.2-0.3 micro meter in size.
• The largest cell is is the egg of ostrich which is about 18 cm in size.
• The size of prokaryotic cell is generally about 1-10 micrometer.
• The size of eukaryotic cell is generally about 10-100 micrometer.

EUTELIC ORGANISM

• The organism which have fixed number of somatic cell on maturity is known as eutelic organism and the phenomenon is called eutely.
• In eutelic organism growth is occurs in two phase:-

1. Before maturity:- The growth is by cell division.
2. After maturity:- the growth is by increasing in cell size.

example:-Rotifers, ascaries and many species of nematodes.

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