Repro 3

Question 1

What stimulates GnRH neurons to release GnRH

Answer 1

Pulsatile activity in kisspeptin neurons

Question 2

LH and FSH act on

Answer 2

Gonads to stimulate hormone secretion and facilitate gamete production

Question 3

What is the least understood influence on reproductive hormones

Answer 3

Environmental

Question 4

What can be studied for environmental influences

Answer 4

Nutritional status, PA, change of day/light cycle, travelling, night shifts

Question 5

Environmental estrogens

Answer 5

Can bind and activate estrogen receptors
- some are anti estrogens
- may influence developing embryo or fetus

Question 6

Anti estrogens

Answer 6

Interfere with second messenger pathways

Question 7

Examples of environmental estrogens

Answer 7

Pesticides, phytoestrogens, processed foods

Question 8

Testes

Answer 8

Produce hormones and gametes

Question 9

Male External genitalia

Answer 9

Penis, urethra, corpus spongiosum, corpora cavernosa, glans, prepuce (foreskin), scrotum

Question 10

What are 2 erectile tissue

Answer 10

Corpus spongiosum, corpora cavernosa

Question 11

Why is prepuce removed

Answer 11

Hygiene, cancer, STI, UTI, HIV

Question 12

What is primary erectile tissue

Answer 12

Corpora cavernosa

Question 13

What keeps urethra open

Answer 13

Corpus spongiosum

Question 14

3 accessory glands

Answer 14

Seminal vesicle (pair)
Prostate gland
Bulbourethral gland

Question 15

What connects testes to urethra

Answer 15

Vas deferens and epididymis

Question 16

When do testes migrate to scrotum

Answer 16

By 8 months of fetal development

Question 17

What temp does sperm development require

Answer 17

2-3 F lower

Question 18

What is failure to descend

Answer 18

Cryptprchidism (usually resolves itself in year)
- if not moved with testosterone treatment or surgically
- unable to produce sperm but still produce androgens

Question 19

What is problem in many men over 50

Answer 19

Benign prostatic hypertrophy

Question 20

What is involved in prostate development

Answer 20

DHT

Question 21

What shrinks hypertrophied prostate

Answer 21

Administration of 5a-reductase inhibitor (finasteride) blocks DHT production

Question 22

What do testes produce

Answer 22

Sperm and hormones

Question 23

Testes are

Answer 23

Paired ovoid structures ~2.5 x 5m
Tough fibrous capsule split into 250-300 compartments

Question 24

Where does final maturation and storage of sperm occur

Answer 24

Epididymis

Question 25

What is within compartments of testes

Answer 25

Seminiferous tubules - 400-600 - 80% of testicular mass - 0.3-1 meter long each

Question 26

where do seminiferous tubules empty

Answer 26

Into epididymis

Question 27

What lies between seminiferous tubules

Answer 27

Interstitial tissue with blood vessels and Leydig cells

Question 28

What is site of sperm production

Answer 28

Seminiferous tubule

Question 29

Where are developing spermatocytes in seminiferous tubules

Answer 29

Stack in columns from outer edge to lumen with Sertoli cells between each column

Question 30

Leydig cell

Answer 30

Found in interstitial tisssue produce testosterone during development then again after puberty

Question 31

What does basal lamina of seminiferous tubule do

Answer 31

Keep out large particles but allows testosterone to enter

Question 32

Sertoli cells contain

Answer 32

Tight junctions with adjacent Sertoli cells forming a blood testis barrier between tubule lumen and interstitial space

Question 33

What do Sertoli cells regulate

Answer 33

- Sperm development - provide sustenance or nourishment

Question 34

What do Sertoli cells produce

Answer 34

Hormones (activin and inhibin), growth factors, enzymes, androgen binding protein

Question 35

What does androgen binding protein do

Answer 35

Binds to testosterone to keep it in the tubule lumen

Question 36

Where do male germ cells (spermatogonium) reside

Answer 36

Inside basal lamina of seminiferous tubules - some remain to undergo mitosis to produce more germ cells some enter meiosis to become primary spermatocytes

Question 37

As spermatocytes differentiate to sperm where do they move

Answer 37

Towards tubule lumen (cells push)

Question 38

What do Sertoli cells do around migrating sperm

Answer 38

Tight junctions break and reform around migrating cells

Question 39

What happens to one spermatogonium when reaching lumen

Answer 39

Becomes 4 spermatids

Question 40

What do spermatids do at apical membrane

Answer 40

- remain embedded in apical of Sertoli cells while completing transformation

Question 41

What transformations happen to spermatids at apical membrane (still not motile)

Answer 41

- lose most of cytoplasm - develop flagellated tail - chromatin condenses - microtubule extension - acrosome forms cap over nucleus - midpiece has mitochondria for energy

Question 42

How long is spermatogonium to free sperm

Answer 42

~64 days (200 million produced/day)

Question 43

Where are sperm released from

Answer 43

Sertoli cells before reaching maturing

Question 44

How is sperm pushed out of Sertoli cells if no motility

Answer 44

Out of tubule lumen by other developing sperm, bulk flow of other fluids, and contraction

Question 45

Where do sperm mature

Answer 45

Epididymis (cells secrete proteins) - during 12 days of transit time

Question 46

What does spermatogonia is require

Answer 46

Gonadotropins and testosterone

Question 47

What does FSH do in males

Answer 47

- bind to receptors on Sertoli cells causing them to generate paracrine molecules needed for spermatogonia mitosis and spermatogenesis - also produces ABP and inhibin

Question 48

LH does what in males

Answer 48

- targets interstitial Leydig cells resulting in production of testosterone - essential for spermatogenesis

Question 49

What do spermatocytes not have

Answer 49

Receptors for FSH, LH or androgens

Question 50

Sperm leading via vas deferens is joined by

Answer 50

Secretions of accessory glands to make semen

Question 51

Semen

Answer 51

Liquid medium for delivering sperm (99% accessory)

Question 52

What is other role of semen

Answer 52

Protect reproductive tract fro pathogens ascending urethra

Question 53

What chemical substances do accessory gland secretions contain

Answer 53

1. Nutrients 2. Buffers for protection against acidic vaginal environment and residual acidic urine in urethra 3. Chemical to increase sperm motility 4. Prostaglandins (motility and contraction of male and female reproductive tracts) 5. Immunoglobulins, lysozyme and other antibacterial compounds

Question 54

What secondary sex characteristics are affected by androgens

Answer 54

Body shape, facial and body hair growth, muscular development, thickening of vocal cords, behavioural effects (i.e. libido)

Question 55

Androgens promote what

Answer 55

Anabolism Anabolic hormones and promote protein synthesis

Question 56

What other structures have androgen receptors

Answer 56

Brain, kidneys, heart, skin, liver, bones