male reproductive system

Question 1

Scrotum:
divided by…
seam…

Answer 1

Pouch containing testes
L lower than R
Divided by internal median septum
Externally marked by seam (perineal raphe)

Question 2

3 mechanisms regulate temperature for sperm production (<37degrees)

Answer 2

Cremaster muscle
Dartos muscle
Pampiniform complex

Question 3

Cremaster muscle

Answer 3

Strips of internal abdominal oblique muscle

Contracts when cold to draw testes nearer body

Question 4

Dartos muscle

Answer 4

Subcutaneous layer of smooth muscle

Contracts when cold so taught + wrinkled

Question 5

Pampiniform complex

Answer 5

Extensive vein network

Cools blood + testes by acting as a countercurrent heat exchanger

Question 6

Testes
Exocrine...
Endocrine...
Outer cover...
Capsule...

Answer 6

Pair
Exocrine glands = sperm cells
Endocrine glands = testosterone
Outer cover = tunica vaginalis 
White capsule = tunica albuginea

Question 7

Testes lobules
Divided by..
Contains…
Between tubules = ….

Answer 7

Divided by connective tissue septa
Each contains 1-3 seminiferous tubules
Between tubules = interstitial cells/cells of Leydig

Question 8

Site of sperm production

Lined with germ cells

Answer 8

Seminiferous tubules

Question 9

Site of testosterone production

Answer 9

Cells of leydig / interstitial cells

Question 10

Germ cells

Answer 10

Process of becoming sperm

Question 11

Sustentacular/sertoli cells
Provide…
Secrete…

Answer 11

Provide nutrients, waste removal
growth factors
secrete inhibin

Question 12

Inhibin

Answer 12

Regulates rate of sperm production

Question 13

Blood-testis barrier (BTB)
Location…
Prevent…

Answer 13

Tight junctions between adjacent sertoli cells

Prevent proteins + other large molecules getting to germ cells, i.e. prevent attack from immune system

Question 14

Sterility BTB

Answer 14

BTB fails to form adequately in adolescence

Immune system produces antibodies against germ cells

Question 15

Rete testis
What is it??
Sperm moved by…

Answer 15

Network where sperm partially mature

Sperm moved by fluid secreted by sustenacular cells + cilia (dont swim)

Question 16

Decent of testis
Begins…
Foetus…
As decend…

Answer 16

Begin development near kidney

Foetus: testis -> inguinal canal

As decend: every-elongating testicular arteries, veins, lymphatic vessels, nerves, sperm ducts + extensions of internal abdominal oblique muscle

Question 17

Undecended testes

Correct with…

Answer 17

Infertility
Too warm for spermatogenesis
Correct with hormone injections or surgery

Question 18

Spermatic ducts (4)

Answer 18

Efferent ductules
Epididymis
Vas deferens
Ejaculatory duct

Question 19

Efferent ductules

Answer 19

With clusters of ciliated cells

Question 20

Epididymis

Ducts reabsorb…

Answer 20

Head, body, tail
6m coiled duct where sperm matures over 20 days
Fertile sperm stored 50 days
Ducts reabsorb 90% fluid secreted by testis

Question 21

Vas deferens
Unites with…
SMC wall…

Answer 21

Up through inguinal canal, down behind bladder, widens into ampulla, unites with duct of seminal vesicle

SMC wall, during orgasm, peristaltic contractions drive sperm from epididymis to ejaculatory duct

Question 22

Ejaculatory duct

Answer 22

Where vas deferens + duct of seminal vesicle meet

Question 23

Accessory glands (3)

Answer 23

Seminal vesicles

Prostate gland

Bulbourethral gland (cowper)

Question 24

Seminal vesicles

Answer 24

Pair
Posterior to urinary bladder
1 associated with each vas deferens
Secretion = 60% of semen
Thin, milky secretion = 30% of semen

Question 25

Bulbourethral/cowper gland

Answer 25

Inner end of penis Ducts lead to penile urethra During arousal produce clear fluid; lubricates + neutralises acidity of residual volume

Question 26

Urethra - regions

Answer 26

Prostatic: near bladder Membraneous: passes through muscular floor of pelvic cavity Penile

Question 27

Penis

Answer 27

3 columns of erectile tissue - 2 corpus cavernosa - 1 corpus spongiosum Foreskin covers glans Root = blub + crus

Question 28

Secretions

Answer 28

Semen/seminal fluid 2-5ml per ejaculation 60% seminal vesicle fluid 30% prostatic fluid 10% sperm

Question 29

Composition of semen (7)

Answer 29

``` Spermatozoa Fructose Fibrinogen Clotting enzymes Fibrinolysin Prostaglandins Spermine ```

Question 30

Spermatozoa

Answer 30

Digest path through cervical mucus, fertilise egg

Question 31

Fructose

Answer 31

Energy for sperm motility

Question 32

Fibrinogen

Answer 32

Causes semen to clot

Question 33

Clotting enzymes

Answer 33

Convert fibrinogen to fibrin after ejaculation | So semen clot + adhere to vagina

Question 34

Fibrinolysin

Answer 34

Liquefies semen 15mins after ejaculation to liberate sperm

Question 35

Prostaglandins

Answer 35

Reduce viscosity of cervical mucus

Question 36

Spermine

Answer 36

Neutralise vaginal acidity

Question 37

Semen analysis (5)

Answer 37

``` Sperm count Motility Volume Shape Liquefaction ```

Question 38

Vasectomy

Answer 38

Segment of ductus deferens removed Spermatozoa cannot pass Scar tissue forms permanent seal

Question 39

Control by Inhibin

Answer 39

Reduce FSH secretion and sperm production without reducing LH and testosterone secretion Sertoli cells Selectively suppresses FSH When sperm count <20mil, inhibin low and FSH high

Question 40

Puberty

Answer 40

Hypothalamus less sensitive to inhibitory effect of androgens GnRH secretion rate increased Increased FSH (sperm cells formed) and LH (leydig cells secrete testosterone)

Question 41

Viagra

Answer 41

Treatment for erectile dysfunction Inhibits enzyme in order to maintain blood flow and erection