$A$ : Lack of menstruation may be indicative of pregnancy.
$R$ : Menstruation only occurs if the released ovum is fertilised.
Assertion and Reason both are correct and also correct explantion.
Assertion and Reason both are correct but not explanation of assertion.
Assertion is correct, but Reason is incorrect.
Both Assertion and Reason are incorrect.
The human sperms were first seen and discovered by
When a small piece of dorsal lip of blastopore of frog's early gastrula is transplanted into another gastrula of similar age at ventral lip, the result is
Enzyme present in sperm acrosome to dissolve egg membrane is
Meroblastic cleavage refers to one of the following types of division of eggs
Relaxin (a hormone) is secreted by