reproductive physiology

Question 1

what is the sequence of the HPO axis ?

Answer 1

• hypothalamus
• gonadotropin releasing hormone
• anterior pituitary
• FSH + LH
• ovary
• estrogen and progesterone
• uterus

oestrogen has positive feedback on hypothalamus and anterior pituitary on days 12-14 (negative feedback most of the cycle)

Question 2

what are the different phases of the ovarian cycle ?

Answer 2

follicular phase - LH high spike, FSH low spike at end

luteal phase - egg is released leaving the corpus luteum

Question 3

what are the phases of the menstrual cycle ?

Answer 3

menstrual phase
proliferative phase
secretory phase
premenstrual phase

oestrogen peaks in middle with late progesterone rise

Question 4

what happens during oogenesis ?

Answer 4

oogonium stem cells undergo mitosis to produce primary oocytes
meiosis starts at each cycle in response to hormones
two meiotic divisions create 2 polar bodies and a mature egg cell

Question 5

what are the different cells of the testis and what are their function ?

Answer 5

germ cells - produce sperm
Sertoli cells - support sperm producing cells, produce inhibit
Leydig cells - produce testosterone, respond to LH