Question

Which one of the following statements is correct?

• A. In over 60 per cent of angiosperms, pollen grains are shed at the 3-celled stage.
• B. Sporogenous tissue is haploid.
• C. Pollen grains of some species are stored in liquid ammonia.
• D. Tapetum nourishes the developing pollen.

Answer 1

The correct option is D Tapetum nourishes the developing pollen.

Tapetum is the inner layer of the wall of microsporangium. Its function is to provide nourishment to the developing pollen.

In over 60 per cent of angiosperms, pollen grains are shed at the 2-celled stage (one vegetative cell and one generative cell). In such plants, the generative cell divides and forms the two male gametes during the growth of pollen tube in the stigma.

Sporogenous tissue is diploid. The cells of sporogenous tissue undergo meiosis to form haploid microspores which develop into pollen grains.

Pollen grains of certain species are stored in liquid nitrogen $(-{196}^{\circ })$.