Assertion: Photomodulation of flowering is phytochrome-regulated process.
Reason: Active form of phytochrome (Pfr) directly induces floral induction in shoot buds.

Options

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

Answer

C

Explanation

Flowering is a phytochrome regulated process phytochrome is a blue protien pigment with a molecular mass of about 125 k Da(kilodaltons).Phytochrome occurs in two interonvertible form `P_(R)` (Which absorbs red light)And `P_(FR)`(Which absorbs far red light).The studies with mutants of arabidopsis support and prove that the`P_(FR)`is the active form of phytochrome.When `P_(R)`molecules are exposed to red light,most of them absorb it and converted to`P_(FR)`.This causes floral induction of shortday plants and promotes flowering of long-day plants red light is more effective with short-day plants and a mixture of red and far-red with long-day plants.