Class 12th Biology 2017 Set2 Outside Delhi Board Paper Solution
Question 10
“Pollen grains in wheat are shed at 3-celled stage while in peas they are shed at 2-celled stage.” Explain. Where are germ pores present in a pollen grain ?
Answer
At the time of shedding wheat pollen consist of one vegetative and two male gametes ( 3 celled) , While pea pollen consists of one vegetative and one generative cell (2 celled).
Germ pores are present on the exine (where sporopollenin is absent )
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