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VARIATION IN NUMBER:Organisms are of 2 types* Unicellular organisms*Multicellular organismsVARIATION IN SHAPEOrganisms are of 3 types*Nerve cells*Muscle cells*Skin cells
VARIATION IN SIZE:*Here, organisms can vary from a Micrometreto a few Centimeter.
Cell consists of one main part which is known as the ‘Brain of the cell’. Cell membrane ,cytoplasm ,nucleus.
CELL MEMBRANE: It acts as the outer covering of the cell. Which has a porous membrane to it. As the plasma membrane.
CYTOPLASM: Many organelles are present in the cytoplasm. It is a jelly like fluid.
NUCLEUS: It is known as the ‘brain of the cell’. It is surrounded by the nuclear membrane. It also contains the chromosomes, that carry genes, that are transferred during cell division.
Golgi apparatus -> are small tubes, that are responsible for the secretion of chemical substance.
Vacuole -> they store excess water, useful minerals.
Lysosome -> they contain enzymes, at times of emergency they burst and destroy the cell, They are also called as ‘The suicidal bag of the cell’.
Endoplasmic reticulum -> They
help in the transport and storage of cell
products. Ribosome -> They
are granulated substances
present in the cytoplasm.
Mitocondria -> They are tiny rod-shaped
bodies is know as ‘The power house of the cell’. They act as sites of energy.
Centrosome -> They are present only in animal cells, their function is to initiate and regulate cell division.
Plastids -> they are only present in the plant cell, there are of three types of plastids.1) chromoplast2) chloroplast3)leucoplast