AP BIOLOGY

Detailed explanation-1: -Primary growth occurs at the apical meristem (a meristem located at the tip of a stem). A meristem is a region of undifferentiated cells from which new cells arise through cellular division. Secondary growth is an increase in thickness or girth of the plant body due to activity of lateral meristems.

Detailed explanation-2: -Primary growth is a result of rapidly-dividing cells in the apical meristems at the shoot tip and root tip.

Detailed explanation-3: -You’ll recall that the apical meristem is the site of cell division and new cell production at the tips of the plant stems and roots. The cells that make up the meristem are undergoing mitotic cell division to produce more cells. These new cells result in growth and development of plant tissues.

Detailed explanation-4: -Apical meristems give rise to the primary plant body and are responsible for the extension of the roots and shoots. Lateral meristems are known as secondary meristems because they are responsible for secondary growth, or increase in stem girth and thickness.