Growth and Development in Plants MCQs for NEET — Botany Questions with Answers

The NCERT states, 'The constantly dividing cells... represent the meristematic phase of growth. The cells in this region... Their cell walls are primary in nature, thin and cellulosic with abundant plasmodesmatal connections.'

The NCERT text explicitly states: 'one single maize root apical mersitem can give rise to more than 17,500 new cells per hour... In the former, growth is expressed as increase in cell number.'

The NCERT text describes the maturation phase cells as those that 'attain their maximal size in terms of wall thickening and protoplasmic modifications.' These features distinguish them from elongation phase cells, which are primarily characterized by increased vacuolation and cell enlargement.

The NCERT text mentions, 'Development is the sum of two processes: growth and differentiation.'

The NCERT text states, 'in dicotyledonous plants and gymnosperms, the lateral meristems, vascular cambium and cork-cambium appear later in life. These are the meristems that cause the increase in the girth of the organs in which they are active. This is known as secondary growth of the plant.' Apical meristems are responsible for primary growth (elongation).

The NCERT text describes meristematic cells as 'rich in protoplasm, possess large conspicuous nuclei. Their cell walls are primary in nature, thin and cellulosic with abundant plasmodesmatal connections.' Increased vacuolation is characteristic of the elongation phase.

The NCERT text states: 'cells in a watermelon may increase in size by upto 3,50,000 times... the latter expresses growth as increase in size of the cell.'

Differentiation is the act leading to maturation where cells undergo structural changes. The text states: 'For example, to form a tracheary element, the cells would lose their protoplasm. They also develop a very strong, elastic, lignocellulosic secondary cell walls, to carry water to long distances even under extreme tension.'

The NCERT text clearly states: 'The living differentiated cells, that by now have lost the capacity to divide can regain the capacity of division under certain conditions. This phenomenon is termed as dedifferentiation.'

The NCERT text provides this specific example: 'For example, formation of meristems – interfascicular cambium and cork cambium from fully differentiated parenchyma cells' as an instance of dedifferentiation.