🔬 Biology · Human Reproduction · NEET

Menstruation is triggered by a fall in the blood levels of:

Answer: progesterone and estrogen.

A progesterone and estrogen
B insulin and glucagon
C thyroxine and TSH only
D adrenaline hormone only

Correct answer: A. progesterone and estrogen

Explanation: When progesterone and estrogen fall, the uterine lining breaks down, causing menstruation.

Sagittal section of the human male reproductive system showing the testis, epididymis, vas deferens, seminal vesicle, prostate gland, bulbourethral gland, urethra, urinary bladder and penis

The human male reproductive system: sperm formed in the testis mature in the epididymis and travel via the vas deferens, mixing with secretions of the seminal vesicle, prostate and bulbourethral glands. Image: Wumingbai, CC BY-SA 4.0, via Wikimedia Commons.

Concept context

Male and female reproductive systems, gametogenesis, fertilization, implantation, pregnancy, and reproductive health.

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Menstruation is triggered by a fall in the blood levels of:

Concept context

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