Bamboo species exhibit unusual flowering phenomenon, because it flowers:
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → only once in their life time.
Option (1) once in 12 years in their life time. — Incorrect. NCERT says bamboo flowers only once in its lifetime; it gives no cycle of 12 years. So this option does not match the book.
Option (2) only once in their life time. — Correct. Bamboo flowers only once in its lifetime, like the Pacific salmon fish breeds once.
Option (3) three times in their life span. — Incorrect. Flowering three times would make bamboo a plant that breeds many times. NCERT groups bamboo with the Pacific salmon fish as organisms that breed only once.
Option (4) many times in their life span. — Incorrect. Flowering many times is the usual pattern of most plants.
NCERT Extract:
Life History Variation – “… Populations evolve to maximise their reproductive fitness, also called Darwinian fitness (high r value), in the habitat in which they live. Under a particular set of selection pressures, organisms evolve towards the most efficient reproductive strategy. Some organisms breed only once in their lifetime (Pacific salmon fish, bamboo) while others breed many times during their lifetime (most birds and mammals).”