2. 11/09 F + E

Question 1

1. antr pit gland

Answer 1

produces follicle stimulating hormone and leutinising hormone which influences the 3 phases of the ovarian cycle and the menstrual cycle.

Question 2

primary hormones secreted by hypothalamus

Answer 2

• corticotrophins releasing hormone (CRH)
• gonadotrophin releasing hormone GnRh
• growth hormone releasing hormone GHRH/GH inhibiting hormone GHIH aka somatostatin
• prolactin releasing hormone / prolactin inhibiting hormone PIH aka dopamine
• thyrotropin releasing hormone TRH
• anti diuretic hormone ADH and oxytocin

Question 3

reproduction cycle phases + locations

Answer 3

pituitary; brain
ovarian; ovaries
menstrual; uterus

Question 4

pituitary cycle

Answer 4

1. Hypothalamus receives positive feedback and releases GnRH to anterior pituitary, either releases FSH or LH depending on stage of menstrual cycle.
2. FSH —> Graafian follicle.
3. Oestrogen produced, negative feedback to antr pit. Antr pit stops producing FSH and starts LH, GF ruptures and ovulation occurs. /
4. Egg released and looking for sperm, LH increases.
5. LH —> CL formed, producing estrogen and progesterone, preparing for implantation, however if no implantation the CL degenerates, causing menstruation.

Question 5

Graafian follicle development

Answer 5

primordial follicle, early primary follicle, late primary follicle, secondary primary follicle, Graafian follicle (FP) , rupturing follicle (O) corpus luteum (LS), corpus albicans.

Question 6

ovarian cycle

Answer 6

• follicular/proliferative phase
• ovulation
• luteal/secretory phase

Question 7

follicular/proliferative phase

Answer 7

• follicles enlarge and one matures, or ripens, each month (Graafian Follicle).
• graafian follicle swells and becomes tense.
• oestrogen dominant.

Question 8

ovulation

Answer 8

• releases ovum into fimbulated end of uterine tube. ​

Question 9

luteal/secretory phase

Answer 9

• cells of the ruptured follicle proliferate to make structure irregular in shape and yellow in colour ‘Corpus Luteum’

Question 10

ovarian hormones which influence reproduction cycle

Answer 10

oestrogen, progesterone, relaxin

Question 11

oestrogen effect on repro cycle

Answer 11

• ​inhibits FSH release so only one egg matures in a cycle.
• stimulates the pituitary gland to release the hormone LH.

Question 12

progesterone effect on repro cycle

Answer 12

• acts on the endometrium to prepare for implantation.
• raises body temperature by 0.5°C after ovulation and causes tingling and sense of fullness of breasts prior to menstruation.

Question 13

relaxin influence on repro cycle

Answer 13

• small amounts cause uterine quiescence which is the ideal environment for fertilised oocyte to implant.

Question 14

repro cycle summary; follicular

Answer 14

FSH stimulates growth of several follicles, dominant follicle secretes oestrogen, oestrogen inhibits growth of other follicles (and FSH), oestrogen stimulates development endometrium

Question 15

repro cycle summary; ovulation

Answer 15

surge in LH causes ovulation, rupturing of follicle creates corpus luteum

Question 16

repro cycle summary; luteal

Answer 16

CL secretes P+E, P stimulates development of endometrium
E + P inhibit FSH + LH, CL degenerates over time, CL degrades and P levels drop
without P, endometrium cannot be maintained so endometrium is sloughed away -menstruation
no longer inhibited, FSH can start menstrual cycle again
if fertilisation occurs, the zygote releases a hormone hog which maintains the CL.

Question 17

corticotrophin releasing hormone CRH

Answer 17

stimulates ACTH release from antr pit

Question 18

gonadotrophin releasing hormone GnRH

Answer 18

stimulate FSH and LH release from antr pit

Question 19

growth hormone releasing hormone GHRH/GH inhibiting hormone GHIH aka somatostatin

Answer 19

stimulate growth hormone GH/GHIH release from antr pit

Question 20

prolactin releasing hormone/prolactin inhibiting hormone PIH aka dopamine

Answer 20

stimulate prolactin release from antr pit

Question 21

thyrotropin releasing hormone TRH

Answer 21

stimulate TSH release from antr pit

Question 22

anti diuretic hormone ADH and oxytocin

Answer 22

post pit hormone

Question 23

ovulation monitoring

Answer 23

​ - calendar method
- basal body temperature (progesterone causes temp spike)
- billings method/family planning
- ovulation strip
- ovulation Cassette
- ovulation microscope
- intake of Alkaline food

Question 24

indication by cervical mucus

Answer 24

• cervical mucus test; 12-14 days of cycle. The mucus increases in amount in the preovulatory estrogen dominated phase; watery, clear, copious, acellular, excellent spinnberkeit>8cm long , has fan pattern when dried.
• 13-14 day egg yolk signifies ovulation will occur in the next couple hours.
• cervical mucus decreases in amount, changes in character, no longer dries in a fan pattern in the luteal phase.

Question 25

spermatogenesis

Answer 25

- start at puberty. - production under the effect of LH&FSH. - LH stimulate the production of testosterone from the testes. - some testosterone comes from adrenal gland above the kidney. - stored at epididymis for maturation and motility. - takes an average of 74days {60-80days}. - men may produce between two milliliters and five milliliters of semen each time they ejaculate, and that each milliliter may contain from 20 million to 300 million sperm cells.

Question 26

fertilisation

Answer 26

​ - fertilisation (conception) is fusion of genetic material from male gamete (sperm) and female gamete (oocyte) which forms diploid zygote (fertilised cell). - process takes approx. 12-24hours. - normally occurs in ampulla of uterine tube. - the oocyte is moved along the tube by cilia, at the same time, the cervix, which is under the influence of oestrogen secretes a flow of alkaline mucus that attracts sperm.

Question 27

development of zygote

Answer 27

1 - pre embryonic period; fertilisation to week 2 (zygote) - 2nd week development - implantation 2 - embryonic period; week 2 to 8 (embryo) - 3rd week development - trophoblast

Question 28

1 - pre embryonic period; fertilisation to week 2 (zygote) - 2nd week development

Answer 28

​ - the second week of development is known as the week of twos: - the trophoblast differentiates into two layers, the cytotrophoblast and syncytiotrophoblast. - the embryoblast forms two layers, the epiblast and hypoblast. - the extra embryonic mesoderm splits into two layers, the somatopleure and splanchnopleure. And two cavities, the amniotic and yolk sac cavities, form.

Question 29

1 - pre embryonic period; fertilisation to week 2 (zygote) - implantation

Answer 29

- implantation occurs at the end of the first week. - zona pellucida degenerates. - enzyme secreted by trophoblast cells digests decidua cells of endometrium. - blastocyst enters into the spongy layer of the decidua and becomes embedded - embedding is also termed nidation (nesting). - embedding complete by day 11 following ovulation. - the only evidence of the presence of the blastocyst is a small bulge on the surface of the decidua.

Question 30

2 - embryonic period; week 2 to 8 (embryo) - 3rd week development

Answer 30

- third week of gestation is gastrulation, the process that establishes all three germ layers (ectoderm, mesoderm, and endoderm). - gastrulation begins with formation of the primitive streak on the surface of the epiblast.

Question 31

primitive streak

Answer 31

ectoderm - Brain, spinal cord, skin mesoderm - skeleton, muscles, kidneys, heart endoderm - GI tract, lungs

Question 32

2 - embryonic period; week 2 to 8 (zygote) - trophoblast

Answer 32

Trophoblast (outer cells of blastocyst) develops chorionic villi: - chorionic frondosum - placenta - chorion leave – chorionic membrane Trophoblastic cells differentiate: - syncitiotrophoblast - cytotrophoblast - mesoderm

Question 33

devlopment of zygote

Answer 33

egg, zygote, 2 cell stage, 4 cell stage, morula, blastocyst, embryoblastocyst, trophoblast