3. Male Endocrinology

Question 1

hypothalamus action

Answer 1

secretes gonadotrophin releasing hormone (GnRH)

acts on anterior pituitary gland

Question 2

anterior pituitary gland action

Answer 2

stimulated by GnrH

releases luteinising hormone and follicle stimulating hormone

Question 3

what does FSH do?

Answer 3

acts on testes to enable sperm production

only if testosterone is present

Question 4

what does LH do?

Answer 4

acts on testes to produce testosterone

Question 5

what is the effect of testosterone?

Answer 5

negatively feeds back to hypothalamus and anterior pituitary to decrease GnRH /LH/FSH secretion

Question 6

what is inhibin?

Answer 6

hormone produced by testes

negatively feeds back to anterior pituitary to reduce LH/FSH production

Question 7

effect of testosterone in the embryo

Answer 7

causes development of male foetal anatomy

no hormone secretion = female

Question 8

at what age to testosterone levels begin to drop?

Answer 8

40

Question 9

increased testosterone causes

Answer 9

increased aggression/libido
enlargement of larynx 
male pattern pubic hair 
maturation of genitalia 
muscle development 
sperm production 
acne 
long bone growth