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Cell : The Unit of Life

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CBSE Gujarat Board Haryana Board

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Class 10 Class 12
 What are the advantages of multicellularity?

Multicellular organization increases the efficiency of the organism in the following ways follows :

1. Avoids duplication of work : Only certain cells perform a specific function. Thus, all cells do not have to perform the same function and there is no waste of energy on duplication of work.

2. Increases chances of survival : Death of a few cells does not affect a multicellular organism. The function is taken by new cells of the same lineage.

3. Makes specialized units highly effective: Diffrent cells perform different function. Cells performing similar functions are grouped into tissue which carry out specific function. 

4. Long life : Greater efficiency of the cells, because of division of labour, makes multicellular organisms to live longer.

Who concluded, “Cells are the ultimate units forming the structure of all plant tissues”?

Mathias Schleiden.

What is the function of contractile vacuole in amoeba?


 What are receptor molecules ?

Receptor molecules are specific proteins in the cell's plasma membrane that receive chemical signals from outside the cell. When such chemical signals bind to a receptor, they cause some form of cellular response. 

Who reported that the cell had an outer layer which is known as plasma membrane today?

Theodore Schwann 

State one difference between gram positive and gram negative bacteria.

Gram positive bacteria retains the gram stain whereas the Gram negative bacteria does not.