Question

Explain the phases of growth in meristem of plants.

Answer 1

There are three phases in which plant growth takes place. These are cell division or meristematic phase, cell elongation and cell maturation. The meristematic phase is also called formative phase. The tips of roots and shoots exhibit continuous growth and hence are meristematic. During this phase, mitotic divisions of the pre-existing cells take place to form new cells. The rate of respiration of this phase is very high as the formation of new cells requires intense biosynthetic activity. The cells in this region have thin cellulose walls with many plasmodesmata connections, dense protoplasm and conspicuous. The cells next to this region represent the elongation growth phase, in which there is the formation of new cell walls, vacuoles etc. The region next to the elongation phase represents the maturation phase in which the cells attain their maximal size.