Q. Nitrogen is an essential constituent of all :
Answer: Proteins
Notes: Nitrogen is a major constituent of all proteins, and thus of all living organisms. The deficiency of nitrogen causes yellowing of older leaves, stunted plants, dormancy of lateral buds, purple colouration in shoot axis surface, wrinkling of cereal grains and inhibition of cell division. In humans, its deficiency cause PCM that leads to retarded body growth in form of Marasmus and kawashikor.