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Cell : The Unit of Life

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Biology

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Biology

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CBSE Gujarat Board Haryana Board

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Class 10 Class 12
Describe functions of cell membrane.

Functions of cell membrane.

1. It maintains the structure and form of the cell.

2. It keeps the cell contents in place and distinct from the environment materials.

3. It helps in the transport of materials in and out of the cell. By controlling flow of materials and information into the cell, the cell membrane makes metabolism possible.

4. It permits the exit of secretions and wastes materials.

5. It protects the cell from mechanical injury and other unfavourable factors.

 


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

Mathias Schleiden.

State one difference between gram positive and gram negative bacteria.

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

 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. 

What is the function of contractile vacuole in amoeba?

Excretion.

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

Theodore Schwann