Question

Which statement is correct about testosterone signaling?

a. Testosterone crosses membranes by simple diffusion. When it moves from Leydig to Sertoli cells this is an example of endocrine signaling.

b. Testosterone crosses membranes by simple diffusion. When it moves from Leydig to Sertoli cells this is an example of paracrine signaling.

c. Testosterone crosses membranes by facilitated diffusion. When it moves from Leydig to Sertoli cells this is an example of endocrine signaling.

d. Testosterone crosses membranes by facilitated diffusion. When it moves from Leydig to Sertoli cells this is an example of paracrine signaling.

Which statement is true about the initiation of menopause?

a. Declining ovarian steroidogenesis causes increased gonadotropin levels because there is not enough negative feedback.

b. Declining gonadotropin levels cause reduced follicular development and lower ovarian steroid secretion.

c. Increased ovarian steroidogenesis causes increased gonadotropin levels because there is positive feedback.

Which statement is true about the onset of female puberty?

a. Puberty can be delayed if too much leptin binds with receptors in the hypothalamus because high leptin levels indicate low fat reserves.

b. Puberty can be delayed if not enough leptin binds with receptors in the hypothalamus because low leptin levels indicate low fat reserves.

c. Puberty can be delayed if too much leptin binds with receptors in the posterior pituitary because high leptin levels indicate low fat reserves.

d. Puberty can be delayed if not enough leptin binds with receptors in the posterior pituitary because low leptin levels indicate low fat reserves.

Answer 1

Option a is the correct answer as Testosterone crosses membranes by simple diffusion. When it moves from Leydig to Sertoli cells this is an example of endocrine signaling.

The hypothalamus and pituitary gland control how much testosterone the testes produce and secrete. The hypothalamus sends a signal to the pituitary gland to release gonadotrophic substances (follicle stimulating hormone and luteinizing hormone). Luteinizing hormone (LH) stimulates testosterone production