HORTICULTURE

Detailed explanation-1: -The correct answer is Option 1. Apical meristem is present at the growing tips of stems and roots and increases the length of the stem and the root. The girth of the stem or root increases due to lateral meristem (cambium).

Detailed explanation-2: -The root apical meristem is protected as it passes through the soil by an outer region of living parenchyma cells called the root cap. As the cells of the root cap are destroyed and sloughed off, new cells are added by a special internal layer of meristematic cells called the calyptrogen.

Detailed explanation-3: -Meristems are areas where growth occurs and are composed of undifferentiated cells undergoing active cell division. Apical meristems are at the tips of the roots and stems. They are responsible for primary growth of the plant.

Detailed explanation-4: -There are two types of meristem in plants, the above ground portion in the shoot and the below ground portion of the root [fig. 9.1]. The shoot apical meristem produces leaves, buds, and stem. The root apical meristem produces the root and responds to gravitational cues.