Mineral Nutrition In Plants Question 35
Assertion : Nitrogen-fixing bacteria in legume root nodules survive in oxygen-depleted cells of nodules. Reason : Leghaemoglobin reduces oxygen levels in the nodule cells.
Options:
A) If both the assertion and the reason are true and the reason is a correct explanation of the assertion
B) If both the assertion and reason are true but the reason is not a correct explanation of the assertion
C) If the assertion is true but the reason is false
D) If both the assertion and reason are false
Show Answer
Answer:
Correct Answer: D
Solution:
Rhizobium species (e.g., Leguminosarum, R.lupini etc) live in symbiotic association in the root nodules of leguminous plants like, pea, gram etc.
In the soil the bacteria can fix nitrogen.
After entering the legume root, the bacterium induces cell membrane formation.
A pink-red pigment called leghaemoglobin lines the membrane and protects the bacteroids from the oxygen.
BETA
