Physiology

Question 1

How long does the luteal phase in menstrual cycle last?

Answer 1

14 days

Question 2

Measuring what hormone indicates ovulation occured?
What day of cycle should it be measured?
What level indicates ovulation?

Answer 2

Progesterone
Measure mid-luteal - day 21 of 28 day cycle or take 7 days off length of cycle.
Level >20nmol/L indicates ovulation - sign of corpus luteum forming and therefore that ovulation occurred.

Question 3

What day of menstrual cycle should you measure LH and FSH and what do high levels indicate?

Answer 3

Between day 2-5 of cycle.
High levels indicate ovaries not producing enough estradiol/progesterone

Question 4

Half life of FSH

Answer 4

170 mins

Question 5

Half life LH

Answer 5

60 mins

Question 6

Half life of prolactin?

Answer 6

20 mins

Question 7

What hormone acts on Leydig cells and what hormone do leydig cells then produce in response to this?

Answer 7

LH (Leydig, LH - ‘L-L’)
Leydig cells produce testosterone

Question 8

What cells does FSH act on in males?
What does FSH stimulate these cells to do?

Answer 8

Sertoli cells
Stimulates spermatogenesis in seminiferous tubules

Question 9

How long does it take for spermatogonium to become spermatozoa?

Answer 9

90 days

Question 10

What part of nephron is responsible for passive reabsorption of water?

Answer 10

Proximal convoluted tubule

Question 11

In acute hypoxia how much does the pH of the fetus fall by per minute?

Answer 11

0.1 per minute

Question 12

What is released from ovary into fallopian tube in a regular menstrual cycle?
A. Primary oocyte
B. oogonia
C. Secondary oocyte
D. Primary oocyte
E. Ovum

Answer 12

Secondary oocyte

Question 13

Are primary oocyte and primary spermatocyte diploid or haploid?

Answer 13

Diploid (2n)

Question 14

Are secondary oocyte and secondary spermatocytes diploid or haploid?

Answer 14

haploid (n)

Question 14

At what point does the secondary oocyte complete meiosis II?

Answer 14

When sperm penetrates

Question 15

What month gestatation do primary oocytes undergo meiosis I?

Answer 15

5 months gestation

Question 16

What stage of cell cycle do primary oocytes arrest in until puberty?

Answer 16

Prophase I

Question 17

When does primary oocyte complete meiosis I?

Answer 17

At puberty

Question 18

Secondary oocytes remain in what phase of cell cycle until fertilisation?

Answer 18

Enter meiosis II and arrest at metaphase II

Question 19

When does secondary oocyte complete meiosis II?

Answer 19

At fertilisation

Question 20

LH acts on Theca cells to produce what hormone?

Answer 20

Androgens (Theca - Testosterone)
Progesterone

Question 21

What occurs in granulosa cells under stimulation of FSH

Answer 21

Aromatase converts testosterone to estradiol.
Inhibin also produced

Question 22

What effect does inhibin have on HPO axis?

Answer 22

negative feedback on FSH

Question 23

What hormones does corpus luteum produce?

Answer 23

Oestrogen
Progesterone
Relaxin
Inhibin A and B

Question 24

How long does corpus luteum persist for if fertilisation occurs?

Answer 24

6 weeks Placenta replaces function after 3 weeks

Question 25

What is first sign of puberty in males?

Answer 25

Increase in testicular size

Question 26

Normal ECG changes in pregnancy?

Answer 26

L-axis deviation (~15 degrees), inverted T wave in lead III, Q wave in leads III and aVF.

Question 27

What percentage does plasma volume increase by in pregnancy by 32 weeks?

Answer 27

45% (3.8L)

Question 28

What percentage does cardiac output increase by in pregnancy?

Answer 28

40%

Question 29

What happens to heart rate and stroke volume in pregnancy?

Answer 29

Increase HR increases by 10% Stroke vol increases by 30%

Question 30

What happens to haematocrit in pregnancy?

Answer 30

Decreases

Question 31

What gestation does BP reach lowest point in pregnancy?

Answer 31

24 weeks

Question 32

Is tidal volume changed in pregnancy?

Answer 32

Yes increases - however, no change in resp rate

Question 33

What changes do you get in alveolar cells and lactiferous ducts in breasts first in pregnancy, hypertrophy or hyperplasia?

Answer 33

Hyperplasia

Question 34

Average volume of milk produced/day

Answer 34

500-1000mls

Question 35

How long can it take for milk production to stop once suckling stops?

Answer 35

3-4 weeks

Question 36

What effect does dopamine have on breastfeeding?

Answer 36

Inhibitory - inhibits prolactin

Question 37

What stimulates release of prolactin and oxytocin in breastfeeding?

Answer 37

Suckling This neuroendocrine reflex also triggered by mother hearing baby cry or thinking about breastfeeding

Question 38

Main carbohydrate in human milk?

Answer 38

Lactose

Question 39

Major immunoglobulin in breast milk?

Answer 39

IgA

Question 40

What hormone promotes formation of myometrial gap junctions as labour approaches?

Answer 40

Estrogen

Question 41

What role does CRH play in getting body ready for labour?

Answer 41

increases prostaglandin synthesis and may stimulate myometrial contractility.

Question 42

What effect do prostaglandins have on myometrium

Answer 42

Cause contractions