Assertion (A): The reproductive cycle of female primates is called menstrual cycle.
Reason (R): Menstrual cycle starts only before attaining sexual maturation (puberty).
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → (A) is true but (R) is false.
Assertion (A): The reproductive cycle of female primates is called menstrual cycle. — True. Female primates such as monkeys, apes and human beings show a reproductive cycle in which the uterine lining breaks down and flows out at regular intervals. This cycle is called the menstrual cycle.
Reason (R): Menstrual cycle starts only before attaining sexual maturation (puberty). — False. The cycle starts after puberty, not before it. The first menstruation, called menarche, begins at puberty, and the cycles then go on till menopause at around 50 years of age.
A is true and R is false.
NCERT Extract:
Menstrual Cycle – “The reproductive cycle in the female primates (e.g. monkeys, apes and human beings) is called menstrual cycle. The first menstruation begins at puberty and is called menarche.”
Summary – “… The reproductive cycle of female primates is called menstrual cycle. Menstrual cycle starts only after attaining sexual maturation (puberty).”