Which one of the following statement is wrong ?

(a) When pollen is shed at two-celled stage , double fertilization does not take place .

(b) vegetative cell is larger than generative cell

(c) Pollen grains in some plants remain viable for months .

(d) Intine is made up of cellulose and pectin 

Only (a)

The correct answer is Option (3) -Only (a)

a-When pollen is shed at the two-celled stage, double fertilization does not take place.It is incorrect. In flowering plants, double fertilization occurs when one sperm cell fuses with the egg cell to form the zygote, while the other sperm cell fuses with the central cell to form the endosperm. The statement suggests that when pollen is shed at the two-celled stage, double fertilization does not occur. However, this statement is incorrect. Double fertilization can still take place even if the pollen is shed at the two-celled stage. The generative cell within the pollen grain divides to form two sperm cells, which can participate in double fertilization even after pollen shedding.

b-Vegetative cell is larger than generative cell is correct. The generative cell is actually smaller than the vegetative cell.

c-Pollen grains in some plants can remain viable for months, even years. This is because the pollen grains are protected by a tough outer layer called the exine. The exine is made up of sporopollenin, which is a very durable substance that is resistant to decay.

d-The intine is the inner layer of the pollen wall. It is made up of cellulose and pectin.