MCQ
Onset of menstruation is due to:
- AFall in level of progesterone
- BIncrease in level of progesterone
- CIncrease in level of FSH
- DNone of these
Explanation:
The uterine lining dies due to the deficiency or reduced level of progesterone in blood and is sloughed off.
Blood vessels rupture, causing bleeding.
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$II.$ Inheritance of acquired characters
$III.$ Branching descent
$IV.$ Natural selection
$V.$ Mutation
$VI.$ Reproductive isolation
The two key concepts of Darwinism from the given options are