Enlist the key po

- Cell theory was proposed by Schleiden and Schwann in 1838-39. Following are the key points of this theory:

● All the plants and animals are composed of cell products.

● An organism is an outcome of all activities taking place inside the cell.

● Cell is the structural and functional unit of life.

● All cells arise from pre-existing cells (Rudolf Virchow in 1855).

OR

Growth in a plant occurs throughout their life due to the presence of meristematic tissue in specific regions of the plant body. On the basis of position in the plant body, meristems are of three types - apical, intercalary and lateral.

Intercalary meristem occurs at the base of leaves and internodes or below the nodes whereas lateral meristem occurs on the sides both in stem and root. It gives rise to vascular tissues.