7. fertilisation & sperm components (lecture)

Question 1

what is the normal volume of semen per ejaculate?

Answer 1

2-4ml

Question 2

what is the normal sperm count per ml of ejaculate?

Answer 2

20-200 x 10^6

Question 3

what is the total sperm count per ejaculate?

Answer 3

> 40 x 10^6

2-4ml x (20-200 x 10^6)

Question 4

how should sperm within a normal semen sample be?

Answer 4

> 60% sperm swimming forward vigorously

<30% abnormal morphology

Question 5

what should happen to normal semen within an hour?

Answer 5

liquefaction within 1 hour

coagulation before liquefaction

Question 6

what is oligozoospermia?

Answer 6

low sperm count

<20 x 10^6 sperm per ml

Question 7

what are the sperm morphological defects?

Answer 7

giant head
micro-sperm (small head)
double head
double body
long head
rough head
abnormal middle piece (coiled body)

Question 8

which glands are involved in secreting components of semen?

Answer 8

bulbourethral glands (Cowper’s glands)
Seminal vesicles
prostate

Question 9

what are the different percentage of semen component each gland is involved in secreting?

Answer 9

Bulbourethral glands - 5%
seminal vesicles - 60%
prostate - 25%

Question 10

describe the semen secreted by Bulbourethral glands

Answer 10

5% total volume
alkaline fluid
mucous lubricates the tip of penis and urethral lining

Question 11

why does semen need to be alkaline?

Answer 11

neutralise urine from male urethra and acidic secretions in female vagina (reproductive tract)

Question 12

describe the semen secreted by seminal vesicles

Answer 12

60% total volume
alkaline fluid
fructose, prostaglandins, clotting factors

Question 13

why is fructose require in seminal vesicles secretions?

Answer 13

ATP production

energy for sperm to move into vaginal canal –> cervix –> uterus –> fallopian tube

Question 14

why is prostaglandins require in seminal vesicles secretions?

Answer 14

increase sperm motility

increase female genital SM contraction

Question 15

what is an example of semen clotting factor and why is it necessary?

Answer 15

semenogelin

cause semen to coagulate

Question 16

describe the semen secreted by prostate

Answer 16

25% volume
milky, slight ACIDIC fluid
proteolytic enzymes
citric acid
acid phosphatase

Question 17

what are the proteolytic enzymes in prostatic semen secretion?

Answer 17

PSA, pepsinogen

Question 18

why are proteolytic enzymes required in prostatic semen secretion?

Answer 18

breakdown clotting factors from seminal vesicles, re-liquefying semen in 10-20mins (post-ejaculation)

Question 19

what is the function of citric acid within prostatic semen secretion?

Answer 19

ATP production

Question 20

typically, which days does endometrial proliferation occur in uterine cycle?

Answer 20

days 7-14 when there is a rise in oestrogen

Question 21

around which day does ovulation take place?

Answer 21

14

Question 22

what is days 14-28 typically?

Answer 22

uterine secretory phase - oestrogen and progesterone released from corpus luteum

Question 23

what is significant about uterine secretory phase (days 14-28)?

Answer 23

hospitable environment for fertilisation and implantation

Question 24

what is the ideal site of fertilisation?

Answer 24

ampulla of fallopian tube

Question 25

what stimulates uterine contraction?

Answer 25

oxytocin

Question 26

where is the site of semen deposition?

Answer 26

vaginal canal

Question 27

appearance of cervical mucus during days 7-14?

Answer 27

oestrogen only, so abundant clear non-viscous cervical mucus

Question 28

appearance of cervical mucus during days 14-28?

Answer 28

oestrogen and progesterone

thick, sticky mucus plug