Question

Physiologically active form of phytochrome is

• A. $P_{730}/P_{fr}$
• B. $P_{660}/P_r$
• C. $P_{700}$
• D. $P_{680}$

Answer 1

Answer: (A)

$P_{730}/P_{fr}$

Plants grow toward sunlight because the red light from the sun converts the chromoprotein into the active form (Pfr), which triggers plant growth; plants in shade slow growth because the inactive form (Pr) is produced. If seeds sense light using the phytochrome system, they will germinate.

So, the correct answer is 'P730/P'fr