Assertion : Conifer trees produce a large quantity of wind-borne pollen grains
Reason : The pollen grains have wings.

Options

A. If both assertion and reason are true reason is the correct explanation of assertion
B. If both assertion and reason are true but reason is not the correct explanation of assertion
C. If assertion is true but reason is false
D. If both assertion and reason are false.

Answer

A

Explanation

Both assertion and reason are true and reason is the correct explanation of assertion.
Conifer or Pinus is a heterosporous plant producing mega and microspores inside megasporangium and micro-sporangium respectively. Each micro-sporangium is a small, sessile and elongated sac like structure having two layered wall. inside the wall lie tapetum which is a nourishing layer. Inside the cavity are large number of dusty andtwo winged micro-spores present. On maturity the microsporangium wall bursts from the uppar side forming a longitudinal slit. A large number of yellow pollen grain are liberated which are carried by wind the to the presence of wings.