reproductive physiology

Question 1

DIAGRAM-pathway of sperm, storage

Answer 1

stored in epidydimis, then goes through vas deferenes, mixes with fluid from seminal vesicle, then goes via ejaculatory duct into urethra, where mixes with secretions from prostate

Question 2

meiotic divisions in females

Answer 2

both are paused, meiosis 1 halts at prophase during embryo, and continues during puberty, forming secondary oocyte- secondary oocyte then pauses at METAPHASE, and forms egg during fertilisation

Question 3

ovary numbers- development to birth

Answer 3

6 million to 1 million

Question 4

sex and brain

Answer 4

control of movements by nigrostriatal tract, dopaminergic system needed for reward/pleasure, neuroendocrine pathway for fertility ie hormones

Question 5

changes during erection and cllitoris

Answer 5

increasd PNS via pudendal nerve= more NO= more cGMP= more blood flow in corpus cavernosum- same occurs for clitoris

Question 6

LH and FSH- what cells they act on

Answer 6

LH acts on only Leydig cells in testes to produce testosterone to help production of sperm FSH act on Sertoli cells in seminiferous tubules to produce ABP to help with sperm production

Question 7

• feedback in males

Answer 7

Negative feedback- inhibin by Sertoli cells, testosterone as well from Leydig cells

Question 8

quality and quantity of sperm with age

Answer 8

declines

Question 9

differences between male and female axis

Answer 9

functions cyclically+ switches off at around 45

Question 10

LH and FSH roles in males

Answer 10

LH produces progesterone, FSH stimulates development of follicles

Question 11

DIAGRAM how estradiol influences LH/FSH

Answer 11

Ovary produces estradiol (follicular phase) which negatively feeds back- estradiol in LATE FOLLICULAR PHASEthen becomes a POSITIVE regulator: then ovary produces progesterone which -feeds back (luteal phase)

Question 12

role of thecal and granulosa cells

Answer 12

Thecal cells produce androgenic precursors; granulosa cells produce estrogens and progesterone

Question 13

DIAGRAM stages of follicular development, and how long it takes

Answer 13

primordial follicle becomes preantral and halts- in puberty then mecomes antral, and then corpus luteum

Question 14

DIAGRAM endometrial cycle- FSH, LH, their roles, and then oestrogen and progesterone roles

Answer 14

FSH and LH peak to cause ovulation: combination of oestrogen and progesterone at end helps regulate uterus eg thickness

Question 15

DIAGRAM oogenesis

Answer 15

ed

Question 16

DIAGRAM spermatogenesis

Answer 16

ef

Question 17

sperm and egg fertilisation

Answer 17

Sperm goes to egg and has enzymes to get through outer layers eg zona pellucida ie acrosome reaction, allowing head of sperm to go into cytoplasm- zona pellucida changes to prevent further sperm coming in

Question 18

DIAGRAM what occurs after fertilisation

Answer 18

the meiotic arrest is removed, female and male pronucleus (n) and second polar body (spare chromosomes left over during each phase of meiosis) form- these pronuclei (including male) are already duplicated: they then form mitotic spindle, and divide to form 2 diploid cells