How is the cell structural and functional unit of life? Class 9

How is the cell structural and functional unit of life? Class 9

Question 1.

How is the cell structural and functional unit of life? Class 9

Answer:

Cells form the structure of all living organisms, as all organisms are made up of one or more cells. They also perform all vital functions such as respiration, nutrition, excretion, and reproduction. Therefore, the cell is both the structural and functional unit of life.

Question 2.

How does a cell multiply? Class 9

Answer:

Cells multiply through the process of cell division, of which there are two main types. In mitosis, one cell divides to produce two daughter cells that are genetically identical to the parent cell - same DNA, same number of chromosomes. This type of division is used for normal growth, repair of damaged tissues, and replacement of old cells. In meiosis, the parent cell divides twice to produce four daughter cells, each with half the number of chromosomes of the parent. This type occurs only in reproductive organs and is used to produce gametes (sperm and egg cells) for sexual reproduction.