testicular and ovarian function

Question 1

what are the 2 major functions of the reproductive organs

Answer 1

gametogenesis

secretion of hormones

Question 2

what is the stem cell of sperm called

Answer 2

spermatogonium

Question 3

what are the 3 stages of spermatogenesis

Answer 3

mitotic proliferation
meiosis
packaging

Question 4

what occurs during mitotic proliferation in spermatogenesis

Answer 4

spermatogonium mitotically divide –> spermatogonia
- one daughter cell remains at the outer edge of the seminiferous tubule to maintain the germ cell line
- other cell moves towards the lumen to produce sperm
spermatognoia divide to become primary spermatocytes

Question 5

what occurs during the meiosis phase of spermatogenesis

Answer 5

• primary spermatocytes complete first meiotic division to become secondary spermatocytes
• secondary spermatocytes complete second meiotic division to become spermatids

Question 6

what occurs during the packaging stage of spermatogenesis

Answer 6

spermatids differentiate into spermatozoa

Question 7

when does spermatogenesis begin

Answer 7

at puberty

Question 8

what are the 3 major differences between spermatogenesis and oogenesis

Answer 8

• mitotic proliferation of oogoonium occurs prior to birth to make primary oocytes
• primary oocytes are arrested in the first meiotic division
• one oocyte produces 4 ovum (sperm = 4)

Question 9

when are the 1st and 2nd meiotic divisions completed in females

Answer 9

first - completed just prior to ovulation

second - completed after fertilization

Question 10

what hormones does the ovary and the testes produce and which cells of each produce them

Answer 10

• ovary - oestrogen and progesterone (theca and granulosa cells)
• testis - testosterone and DHT (sertoli and leydig cells)

Question 11

what are the 2 peptide hormones produced by the gonads

Answer 11

inhibin and activin

Question 12

what enzyme converts testosterone to DHT

Answer 12

5-alpha reductase

Question 13

what are the accessory glands for the male repro system

Answer 13

prostate
seminal vesicle
bulbourethral gland

Question 14

where abouts in the tests does spermatogenesis occur

Answer 14

in the sertoli cells of the seminiferous tubules

Question 15

where does sperm maturation occur

Answer 15

in the epidydmis and vas deferens

Question 16

leydig cells produce

Answer 16

testosterone

Question 17

what are the effects of testosterone prior to birth in males

Answer 17

• masculinizes repro tract and ext genitalia

- promotes descent of testes into scrotum

Question 18

what are the sex-specific effects of testosterone in males

Answer 18

• promotes growth and maturation of repro system

- spermatogenesis

Question 19

what are the secondary sexual effects of testosterone in males

Answer 19

• hair growth
• voice deepening
• muscle growth
• body configuration

Question 20

what are the nonreproductive effects of testosterone

Answer 20

• protein anabolic effects
• bone growth
• closure of epiphyses (with oestrogen)
• sebaceous gland secretions

Question 21

functions of bulbourethral glands

Answer 21

• produces lubricant
• produces buffers
• produces water

Question 22

functions of prostate gland

Answer 22

• produces water
• produces buffers
• produces citric acid
• produces enzymes

Question 23

functions of seminal vesicles

Answer 23

• produces water
• produces fructose and vitamin C
• produces enzymes
• produces prostaglandins

Question 24

what are the 2 phases of the menstrual cycle and which hormones drive them

Answer 24

• follicular/proliferative (oestrogen)

- luteal/secretory (progesterone and oestrogen)

Question 25

where are the granulosa and theca cells of the follicle in relation to the antrum

Answer 25

granulosa cells close to the antrum | theca cells close to the surface epithelium

Question 26

what occurs during the follicular phase of the menstrual cycle (in general)

Answer 26

- follicle growth in the ovary | - uterine lining proliferates

Question 27

what occurs during the luteal phase of the menstrual cycle (in general)

Answer 27

- ruptured follicle transforms into the corpus luteum in preparation for pregnancy - uterine lining secretory

Question 28

which phase of the menstrual cycle is always 14 days

Answer 28

luteal

Question 29

what hormonal events take place during the follicular phase and what does this cause

Answer 29

- FSH stimulates follicular development to secondary and tertiary follicle - granulosa cells produce oestrogen (keeps FSH and LH low - negative feedback) - LH stimulates thecal cells to produce androgen which are converted to oestrogen by aromatase in granulosa cells - one dominant follicle develops - menstruation and then proliferation of uterus

Question 30

what hormonal events take place to cause ovulation

Answer 30

- oestrogen levels get to a level that is so high that feedback switches to positive feedback --> causes primary oocyte to complete first meiotic division and ovulation - low oestrogen - high inhibin inhibits FSH and decreases new follicle development - low progesterone --> causes positive feedback on GnRH and LH

Question 31

what causes the change in the mucus from the cervix with ovulation

Answer 31

oestrogen

Question 32

what is the cervical mucus like during ovulation

Answer 32

becomes abundant, clear non viscous mucus

Question 33

what hormonal events take place in the early luteal phase and what do they cause

Answer 33

- granulosa cells become the corpus luteum --> produces progesterone - high progesterone and oestrogen maintain the endometrium and cause decreased GnRH, LH and FSH - inhibin inhibits new follicular development - uterus becomes vascular and secretory - cervical mucus becomes thick, sticky and mucousy

Question 34

What happens during the late luteal phase of the menstrual cycle

Answer 34

- corpus lutuem dies --> drop in oestrogen and progesterone --> increased FSH and LH --> new follicular development - menstruation

Question 35

what causes menopause

Answer 35

ovaries cease responding to LH and FSH as no follicles left --> causes low levels of oestrogen and progesterone

Question 36

what "reaction" happens to the sperm to allow penetration of the ovum

Answer 36

acrosomal reaction

Question 37

what is the acrosomal reaction

Answer 37

digestive enzymes are released in order for the sperm to penetrate the ZP and dissolve the cell junctions

Question 38

what reaction happens to prevent polyspermy

Answer 38

cortical reaction

Question 39

how many days can sperm live for

Answer 39

2 days

Question 40

how many days can an ovum live for

Answer 40

1

Question 41

how long is the fertility window

Answer 41

3 days

Question 42

what has to happen to sperm in order for them to have the capacity for fertilisation

Answer 42

capacitation

Question 43

when does a blastocyst form

Answer 43

days 4-5

Question 44

what day of gestation does implantation occur

Answer 44

5-9

Question 45

what are the two cell masses of a blastocyts

Answer 45

inner cell mass | trophoectoderm

Question 46

what weeks of gestation are early pregnancy, embryonic period and fetal period

Answer 46

early pregnancy = weeks 1-2 embryonic period = weeks 3-8 foetal period = weeks 9 to term

Question 47

which pregnancy period is most susceptible to teratogens

Answer 47

embryonic period

Question 48

which pregnancy period is most susceptible to chromosome abnormalities

Answer 48

early pregnancy

Question 49

by which stage are all the organs of the foetus present

Answer 49

by the end of the embryonic period

Question 50

which embryonic period is most susceptible to physiological defects

Answer 50

foetal period

Question 51

what environmental factors can influence normal foetal growth

Answer 51

- multiple pregnancy - maternal under nutrition - oxygenation - placental function - smoking - alcohol - drugs - exercise - infectious agents - environmental chemicals