Question

Life span is defined as the:

• A. Period between birth and sexual maturity
• B. Period between birth and death
• C. Period between sexual maturity and death
• D. Period between sexual maturity and senescence

Answer 1

The correct option is B Period between birth and death

The period of time between the birth and the natural death of an organism is called its lifespan. Different organisms have different lifespans.
Birth is the beginning of the lifespan, and gradually an organism attains different stages of development and maturity and finally, death occurs.

The period from birth to sexual maturity(pre-reproductive phase) is called the juvenile phase (or vegetative phase in the case of plants), then a reproductive phase where an organism is reproductively active and can reproduce. After that, the senescent stage occurs that includes ageing and finally, death occurs.