Reproduction: Test 1 : Parker Q2-6

Question 1

Q2:

GnRH precursor cells migrate from where to where?

Answer 1

migrate from the OLFACTORY PLACODE in the CNS into the HYPOTHALAMUS

Question 2

Q2:

Define Kallman Syndrome

Answer 2

(idiopathic Hypogonadism + Anosmia)

– Kallman syndrome occurs when the migration of gnRH from the olfactory placode in the CNS into the hypothalamus fails.

Question 3

Q2:

GnRH neurons exhibit what two things?

Answer 3

Spontaneous and Autorhythmicity

Question 4

Q2:

During the 3rd week, Intermediate mesoderm gives rise to what?

Answer 4

urogenital ridge (home of future ovaries and testes)

Question 5

Q2:

During the 4th-6th week, germ cells are migrating from where to where?

Answer 5

Yolk sack endoderm to urogenital ridges

Question 6

Q2:

What is another term for the mesonephric ducts and what does this duct give rise to?

Answer 6

Wolffian ducts

Give rise to male ducts and seminal vesicles

Question 7

Q2:

What is another term for the paramesonephric duct and what does it give rise to?

Answer 7

Mullerian ducts

Oviducts, uterus, part of vagina

Question 8

Q2:

What does the mesonephros give rise to?

Answer 8

renal functions for male and female

Question 9

Q2:

What is AMH?

Answer 9

antimullerian hormone

- induces the regression of the development of mullerian structures so the male develops

Question 10

Q2:

What kind of cells secrete AMH and where?

Answer 10

Sertoli cells of the testes

Question 11

Q2:

What happens if there are no AMH present?

Answer 11

Then the wolffian structures will repress and FEMALE develops

Question 12

Q2:
In week 9,
What cells of the testes secrete testosterone and dihydrotestosterone

Answer 12

Leydig cells

Question 13

Q2:

What’s the role of testosterone in this process?

Answer 13

development of of Wolffian ducts

Question 14

Q2:

What’s the role of dihydrotestosterone?

Answer 14

growth and development of penis, prostate and scrotum

Question 15

Q2:

What’s a female hormone?

Answer 15

Estradiol

Question 16

Q2:

What’s a male hormone?

Answer 16

Testosterone

Question 17

Q3:

Define the term pseudohermaphrodite
Genetic Sex?
Gonadal type?
Phenotypic Sex?

Answer 17

It’s when the genotype and phenotype do not match up. Incongruity of genotype and phenotype.

• XY
• Testes
• Inadequate virilization resulting with feminization

Question 18

Q3:

What defects result to pseudohermaphrodite?

Answer 18

• Defects in testosterone
• Defects in 5 alpha reductase –> decrease in DHT production
• Defects in androgen receptors
• AMH defect
• maternal drugs

Question 19

Q3:

When would one realize that they are a pseudohermaphrodite?

Answer 19

• may only be discovered at puberty (amenorrhea) – missing your period for three cycles in a row.

Question 20

Q3: What are the concerns with their health (pseudohermaphrodite)?

Answer 20

• psychosocial

- emotional and physiological implications for individuals beginning at birth.

Question 21

Q3: In pseudohermaphrodites, when should the gonads be removed and why?
- TESTES?

Answer 21

• by age 18. high dose risk of malignany.
• If taken out too early, limited breast linear growth, loss of gametes, decreased libido and natural loss of estrogen.
• TESTES : So since XY has testes, but it still has mullerian structures…. if testes get removed to early, limit and decrease in necessary hormones for body to function effectively.

Question 22

Q4:

What major hormones are involved during the menstrual cycle?

Answer 22

• FSH, GNRH, LH, and progesterone

Question 23

Q4:

What are the various parts of the menstrual cycle:
1st half of cycle? (Events and Phases)
2nd half of cycle? (Events and Phases)

Answer 23

• Ovarian events: Follicular (ovarian) – Ovulation – Luteal Phases
• Endometrial events (uterine part): Proliferative –Secretory phases

Question 24

Q4:

Ovarian Cycle: Describe the Follicular phase (12-14 days):

Answer 24

• GnRH is released from the hypothalamus
• Stimulates pituitary FSH production and release and initiates the growth/development of follicles (4-10)
• Induction of LH receptors on Ovarian Granulosa Cells
• Dominant follicle is recruited for ovulation while other follicles degenerate
• Estradiol and Inhibin levels INCREASE ( (-) Negative feedback to pituitary)
• LH INCREASES, then surges to result in ovulation

Question 25

Q4: Ovarian Cycle: Describe the Ovulation phase (<24 hrs)

Answer 25

LH surge --- Ovum released from dominant follicle | - Basal body temp increases in response to increase progesterone

Question 26

Q4: Ovarian Cycle: Describe the luteal phase (12-14 days) --FIXED

Answer 26

- Follicle reorganizes to become a corpus luteum - High levels PROGESTERONE influence endometrial growth - if conception does not occur --> CORPUS LUTEUM INVOLUTES - Follicular apoptosis (Programmed cell death) - Progesterone secretion drops; Estradiol levels drop - Hypothalamus and pituitary escape influence of negative feedback --> FSH rises and cycle begins again.

Question 27

Q4: What happens in between the ovarian to endometrial cycle

Answer 27

- Increase follicular development - increase estradiol (proliferative corresponds to follicular phase) - menstruation triggered when estrogen and progesterone levels decrease (secretory corresponds to luteal phase)

Question 28

Q5: What is considered normal in terms of the menstrual cycle timing, amount of bleeding?

Answer 28

- Day 1 if first day bleeding, Cycle is 24-38 days; flow 2-7 days - blood loss: 20-80ml(avg 30cc) - Follicular phase is 12-14 days (variable), ovulation is <24hrs - Luteal phase is 12-14 days (fixed)

Question 29

Q5: What is considered abnormal in terms of the menstrual cycle timing, amount of bleeding?

Answer 29

Abnormal: >80cc/period = Heavy menstrual bleeding -- normal until: pregnancy occurs, hormonal manipulation/imbalance interferes with cycle, uterine lining unable to grow and shed, ovarian function ceases (menopause/surgery)

Question 30

Q5: What stops menstrual flow?

Answer 30

PGF2alpha PGE2alpha Tromboxane A2

Question 31

Q6: Puberty: What turns it on?

Answer 31

Begins with DISINHIBITION of Pulsatile GnRH secretion from hypothalamus. (CNS suppression of GnRH is lifted --> Pulsatile release of GnRH)

Question 32

Q6: Puberty: What are the central triggers?

Answer 32

Central control mechanism: inhibitory: GABA, NPY Excitatory: Glutamate, Neurokinin B, Kisspeptins (Kiss-1 mutations do not undergo puberty) - May have role in therapy for precocious/delayed puberty and infertility.

Question 33

Q6: Puberty: What are the peripheral trigger?

Answer 33

Peripheral signals: Leptin, Insulin, Ghrelin, Galanin-Like peptide, Free fatty acids

Question 34

Q6: Puberty: What is considered premature or delayed? FEMALE

Answer 34

FEMALE: - Average onset of female puberty is 10 with completion by age 16, growth over 4 years. - Premature: Before 8. - Delayed: No breast development prior to age 13, no pubic hair by age 14, no menarche by age 16 (if pubes/breasts have developed) - No menarche by age 14 (with absence of any secondary sexual characteristics, more than 5 years between thelarche and menarche

Question 35

Q6: Puberty: What is considered premature or delayed? MALE

Answer 35

MALE: - Average onse for male puberty is 12 with completion by age 18, growth over 6 years. - Premature: if before 9 - Delayed if: no testicular enlargement by age 14, no pubic hair by age 15, more than 5 years between initial and complete growth of genitals

Question 36

Q6: Puberty: What situations prevent or speed up puberty?

Answer 36

Speed up: overweight; closer to the equator; exposure to chemicals that mimic estrogens (PCBs, PBA, Hormones in cattle) Later: Underweight --poor nutrition; high altitude; chronic disease; parasitic infections - also Nature vs Nurture: controlled by: genetics, environment, hormones. and overall health; some familial concordance/racial and ethnic differences exist.

Question 37

Q6: Puberty: List pubertal stages and order of occurrence?

Answer 37

- Adrenarche (hair and body odor between age 6-10). Activation of Adrenal Cortex, Production of adrenal androgens, occurs prior to puberty, stimulates pubarche. - Gonadarche (reactivation of pulstile GnRH secretion from hypothalamus). Facilitates in growth spurt, thelarche, Menarche/Spermache - Pubarche: (Appearance of pubic hair) - Thelarche: (Appearance of breast tissue) (earliest secondary sexual characteristics in most girls under influence of estradiol & estrone) - Menarche (females only). Onset of first menstrual period. - Spermarche (males). Age of 1st ejaculation (Nocturnal) A-->G-->P-->T-->M-->S

Question 38

Q6: Puberty: How are the evaluations for precocious and delayed puberty similar? How are they different? PRECOCIOUS PUBERTY

Answer 38

Precocious puberty: 1. 2nd sexual development before age 8 in girls, age 9 in boys 2. Clinical staging by tanner criteria. 3. 3 types: GnRH dependent (central), GnRH independent (peripheral), isolated. 4. Require bone age to determine.

Question 39

Q6: Puberty: How are the evaluations for precocious and delayed puberty similar? How are they different? DELAYED PUBERTY

Answer 39

DELAYED PUBERTY 1. Absence/incomplete 2nd sexual development when 95% should have developed (no menarche by age 14 w/o 2nd sexual, no menarche by age 16 pubes breasts developed). 2. Clinical staging by tanner criteria. 3. Etiologies: hypothalamus, pituitary, gonads, thyroid gland, chromosomal. 4. Require bone age/karyotype to determine (either hyper/hypogonadotropic hypogonadism). 5. Turners (poor skeletal, pubarche), Kallmann’s (lack sense of smell), Prader Willi/angelman (obesity, hypogonadism).

Question 40

Q6: Additional notes on puberty:

Answer 40

• Puberty (physical growth and sexual maturation, variable age), adolescence (puberty to adulthood) • Estrone (E1) = after menopause (ovaries, adipose, breasts). • Estradiol (E2) = before menopause (T to E2 in brain, breast, muscle). • Estriol (E3) = placental production. o Potency to E2 > E1 > E3