Getting Pregnant, Sex And Fertillisation

Question 1

What do sperm selectively metabolise?

Answer 1

Cholesterol and phospholipids

Question 2

Give 2 ways in which sperm gain mobility.

Answer 2

Increased S-S in proteins in tail - more rigid flagellum with a stronger potential beat

CAMP content of tail increases

Question 3

What is the range for volume of ejaculate?

PH?

Answer 3

2-6mL

7-8

Question 4

What receptors do post ganglionic fibres from the pelvic nerve (S2-S4) bind to?

What happens from here?

Answer 4

M3

Rise in intracellular calcium levels leads to activation of NOS and formation of NO.

NO diffuses into vascular smooth muscle and this activated guanylate cyclase ima the smooth muscle cell generated cGMP which causes vasodilation.

Question 5

What are the 3 steps in an erection?

Answer 5

Sinusoidal relaxation
Arterial dilatation
Venous compression

Question 6

Give some causes for erectile dysfunction.

Answer 6

Psychological
Tears in fibrous tissue
Vascular issue
Drugs

Question 7

What is the use of fern test?

Answer 7

Fern like appearance on microscopy of cervical mucus that is allowed to dry on glass.

Allows for detection of aminiotic fluid

Detects if membranes have ruptured.

Question 8

What receptor does the sperm bind to on the zona pellucida?

What does this cause?

Answer 8

ZP3

Acrosin release allows for penetrations of the zona pellucida

Ca2+ dependant exocytosis of protease-containing cortical granular occurs.