Question

Concerning the hormone leptin, which of the following is not correct?

	(a) it is secreted mainly by adipose tissue
	(b) it is a steroid hormone
	(c) it inhibits feed intake when applied intracerebroventricularly
	(d) human females have relatively higher levels than males
	(e) both a deficiency and an excess of leptin may be associated with obesity

Which of the following is incorrect regarding the 2-cell, 2-gonadotropin theory of estrogen biosynthesis?

	a) LH stimulates the theca interna cells
	b) FSH stimulates the granulosa cells
	c) The theca internal cells secrete estradiol-17β
	d) Cholesterol is the starting material for the synthesis of testosterone
	e) An androgen is converted to an estrogen in this biosynthetic process

Answer 1

Answer:

Answer 1. Option B (It is a steroid hormone)

Explanation: Leptin is a steroid hormone which gets released mainly by the adipose cells of the body and its main function is to regulate the feeling of hunger and maintain the energy balance within the human body.

It is reported that the amount of leptin in women is 2-3 times more than that of the men. This is due to the reason that women have more fat as compared to that of men. So more amount of leptin is produced in them. Further, it is established that leptin is a peptide hormone that is they are very much soluble in water and non steroidal in nature and their target cells for mediating their action is the hypothalamus of the brain.

Answer 2. Option D (Cholesterol is the starting material for the synthesis of testosterone)

Explanation: The 2-cell, 2-gonadotropin theory of estrogen biosynthesis establishes a connection between the ovarian steroid hormones; estrogen and progesterone from the precursor androgen hormone named testosterone with the simultaneous involvement of the theca interna and external cells as well as the granulose cells of the tertiary follicle under the influence of the hormone FSH and LH from the pituitary gland.

Henceforth, this theory does not account for the formation of the male androgen hormone testosterone from the cholesterol.