W8 - Reproductive Systems (lecture)

Question 1

What are the 2 reasons we need reproduction?

Answer 1

Propagation of life and genetic variability

Question 2

What are the two main functions of the reproductive system?

Answer 2

Production of haploid gametes and production of hormones

Question 3

What are the two main groups of reproductive hormones?

Answer 3

Steroid and gonadotropins

Question 4

What are all steroid hormones derived from?

Answer 4

Cholesterol

Question 5

Gonadotropins are protein based, give two examples of them in females

Answer 5

Luteinising hormone and follicle-stimulating hormone

Question 6

Is oxytocin a steroid or gonadotropin?

Answer 6

Neither

Question 7

What type of enzymes are CYP enzymes?

Answer 7

Hydroxylate enzymes

Question 8

What type of enzyme are HSD enyzmes?

Answer 8

Hydroxysteroid dehydrogenase enzymes

Question 9

What is required for a specific organ to produce it’s specific steroid hormone?

Answer 9

A complete set of enzymes needed to appropriately modified cholesterol

Question 10

If there is a mutation causing a non-functional SRY gene, what may happen during fetal development of an XY individual?

Answer 10

No production of TDF and so female reproductive tracts form (therefore is XY with female phenotype)

Question 11

Testosterone is both reproductive and non-reprod in terms of it’s actions, what are the reproductive functions? (3)

Answer 11

Secondary sexual characteristics, genitalia growth and maturation and spermatogenesis

Question 12

What are the 3 non-reproductive actions of testosterone?

Answer 12

Libido and bone growth at puberty and protein anabolic effect

Question 13

What receptor mostly mediates effects of testosterone?

Answer 13

Androgen receptor

Question 14

Estradiol and progesterone also have both reprod and non-reprod effects, what are the 2 non-reprod actions?

Answer 14

Increase in adipogenesis and increase bone mineral density

Question 15

Reprod actions of female gonadal steroid can include secondary sexual characteristics, reprod tract growth and maturation and the menstrual cycle, what 3 other things do they have roles in?

Answer 15

Oogenesis, breast growth/lactation suppression for pregnancy and parturition

Question 16

XO leads to Turner syndrome and XXX is a trisomy of X, what happens if someone has XXY or XYY?

Answer 16

XXY - Klinefelter syndrome, XYY - Jacobs syndrome

Question 17

It’s very unlikely but an SRY gene can appear on an X chromosome resulting in an XX SRY+ve male, how would this occur?

Answer 17

Via recombination

Question 18

What are the 3 parts of the ovarian cycle?

Answer 18

Follicular phase, ovulation and luteal phase

Question 19

What are the 3 parts of the uterine/menstrual cycle?

Answer 19

Menstruation, proliferative phase and secretory phase

Question 20

How does the pill prevent ovulation + menstruation?

Answer 20

Increases progesterone always so the cycle is always kept in the secretory phase

Question 21

During pre-puberty, all oocytes are arrested in prophase I and then only one egg cell per month moves into metaphase, why may this be an issue?

Answer 21

Long periods of time that these cells are kept in arrest affect the chance of infertility

Question 22

What cells do FSH and LH act on in the male reproductive system?

Answer 22

FSH - sertoli cells, LH - interstitial cells

Question 23

Interstitial cells produce testosterone, what does testosterone stimulate?

Answer 23

Mitotic and meiotic divisions that transform undifferentiated diploid spermatogonia into undifferentiated haploid spermatids

Question 24

Testosterone has +ve and -ve feedback, +ve on gametogenesis, where does it affect -vely?

Answer 24

HT - producing GnRH and APG - producing FSH/LH

Question 25

What is there high levels of in the 1st trimester?

Answer 25

Human chorionic gonadotropin (hCG)

Question 26

Oxytocin is a peptide HM produced in the HT, where is it released?

Answer 26

Pituitary gland

Question 27

Oxytocin has primary effects on muscle contraction, in what two ways may this be useful? (it can also effect muscle contraction in sexual intercourse)

Answer 27

For labour - contractions of the uterus and lactation - contraction of myoepithelial cells to release milk

Question 28

OT's secondary effects are as a neuromediator in recognition, trust and romantic attachment, what 2 other things is it a neuromediator for?

Answer 28

Parent-infant bonding and roles in addiction/depression

Question 29

The Fergusson reflex is a positive reflex spiral, increased uterine contractions leads to neuroendocrine reflex, describe this

Answer 29

Increased oxytocin secretion has +ve feedback directly on contractions and indirectly by increasing production on prostaglandins which in turn increase contractions