Reproductive physiology

Question 1

Which neural pathway is dominant in the neuroendocrine control of reward and pleasure?

Answer 1

Mesolimbic dopaminergic

Question 2

Which neural pathway is dominant in the neuroendocrine control of movement?

Answer 2

nigrostriatal tract

Question 3

What is the dominant neural region involved in erection?

Answer 3

Limbic system

Question 4

Recall the sequence of neuroendocrine events that lead to erection

Answer 4

PNS acts on SMCs of pudendal artery
NO increased
cGMP increased
Blood flow in corpus cavernosum increased

Question 5

Recall the mechanism of action of viagra

Answer 5

Inhibits phosphodiesterase - a de-activator of cGMP

Question 6

What is the functional equivalent of the penis in females?

Answer 6

Clitoris

Question 7

Recall the main components of the testes

Answer 7

Seminiferous tubules

Leydig cells

Question 8

What is the function and location of the epididymis?

Answer 8

One within each scrotal sac

sperm storage

Question 9

Recall the points at which fluid enters the ejaculate along the vas deferens

Answer 9

1. Epidydmis (sperm)
2. seminal vesicles
3. Prostate gland

Question 10

What cells are found within the seminiferous tubules?

Answer 10

Sertoli cells

Question 11

What cells are responsible for testosterone production and what is their stimulant?

Answer 11

Leydig cells

LH

Question 12

What cells are responsible for spermatogenesis and what is their stimulant?

Answer 12

Sertoli cells

FSH

Question 13

Where is inhibin produced, and upon which hormone does it negatively feedback?

Answer 13

Seminiferous tubules (sertoli cells)
GnRH

Question 14

Why are gonadotropins released in a pulsatile fashion?

Answer 14

Testosterone negatively feeds back on LH, so as one rises the other falls

Question 15

What is the role of sertoli cells in spermatogenesis?

Answer 15

Provide nutritional and hormonal support

Question 16

Recall the precursor cells leading to the production of a sperm cell, and at which point they become haploid

Answer 16

Spermatogonium
Primary spermocyte
Secondary spermocyte (haploid)
Spermatid
Spermatozoa
Sperm

Question 17

At what point in the male lifespan are germ cells present?

Answer 17

Always - sperm production continues throughout life

Question 18

Recall 3 key structures in the fallopian tube?

Answer 18

Ampulla
Isthmus
Fimbriae

Question 19

Recall the 3 layers of the uterus

Answer 19

Mesometrium
Myometrium
Endometrium

Question 20

By what part of the broad ligament is the ovary suspended?

Answer 20

Mesovarium

Question 21

What is the name given to the primordial germ cell destined to become an egg cell?

Answer 21

Oogonium

Question 22

At what point in the female lifespan are germ cells present?

Answer 22

By birth they have all developed into at least the oogonium stage - no germ cells present after birth

Question 23

Recall the precursor cells leading to the production of an egg cell

Answer 23

Oogonium
Primary oocyte
Secondary oocyte and 1st polar body
Graafian follicle continues to grow –> antral follicle
Does not complete meiosis 2 until fertilisation

Question 24

Recall the cells that respond to LH and FSH in the female reproductive system and each of their functions

Answer 24

FSH - Granulosa cells: stimulate conversion of androstenedione to oestrone using aromatases
LH - Thecal cells: stimulate androgen synthesis

Question 25

Recall the phases of the ovarian cycle and their length

Answer 25

Follicular (14 days) | Luteal (14 days)

Question 26

What is the function of the follicular stage of the ovarian cycle?

Answer 26

17-beta-oestradiol production | Produced by thecal and granulosa cells

Question 27

What is the function of the luteal stage of the ovarian cycle?

Answer 27

Production of E2 and progesterone by corpus luteum

Question 28

How is ovulation stimulated

Answer 28

E2 surge --> LH surge | LH triggers ovulation

Question 29

Recall the approximate change in basal body temperature at ovulation

Answer 29

+0.5 degrees celcius

Question 30

What is the normal range of the menstrual cycle?

Answer 30

21-35 days

Question 31

What name is given to a girl's first period?

Answer 31

Menarche

Question 32

Recall the changes in oestrogen feedback on the adenohypophysis throughout the menstrual cycle

Answer 32

At low levels = neg feedback | At high levels = positive feedback

Question 33

Recall the phases of the endometrial cycle and their lengths

Answer 33

Menstrual (5 days) Proliferative (9 days) Secretory (13 days)

Question 34

What is the function of the secretory phase of the endometrial cycle?

Answer 34

Produce nutrients and other factors

Question 35

How is ovulation coordinated between the ovaries?

Answer 35

Alternate release of follicle between 2 ovaries so that there is 56 days between release of each secondary oocyte

Question 36

When do follicles undergo their first meiotic division? By what are they stimulated

Answer 36

Initiated in embryonic development Completed at puberty to produce secondary follicles Linked to LH surge

Question 37

Around how many follicles will be ovulated in a woman's full lifetime?

Answer 37

400

Question 38

When a follicle is ovulated, in what stage of meiosis is it halted?

Answer 38

Metaphase 2 of meiosis

Question 39

How long does it take for a primordial follicle to develop into a secondary oocyte?

Answer 39

Just over a month

Question 40

Why are sperm most likely to be able to enter the uterus mid-cycle?

Answer 40

Cervical mucus is usually hostile to sperm, changes mid-cycle to permit sperm entry

Question 41

What does sperm bind to on the secondary oocyte surface?

Answer 41

ZP3 glycoprotein

Question 42

Recall the events following sperm binding to a secondary oocyte that lead to fertilisation

Answer 42

Calcium influx Meiosis II resumed Sperm releases hyaluronidase Penetrates ovum Zona pellucida hardens to prevent further sperm entry Female pronucleus produced along with 2nd polar body

Question 43

When do the maternal and paternal pronuclei first fuse in the fertilised egg?

Answer 43

First mitotic division

Question 44

What must happen in order for maternal and paternal pronuclei to fuse?

Answer 44

Decondensation of nuclear material