Male anatomy

Question 1

Testes

Answer 1

Primary sex organ for males
Where sperm are made
Inside of the scrotum sac
Descend 1-2 months before birth

Question 2

Cremaster Muscle

Answer 2

The cremaster muscle surrounds the testes; contracts to pull testes closer to body
Testes must be kept 3º below body temp

Question 3

Seminiferous Tubules

Answer 3

Sperm production occurs in the seminiferous tubules
Each testis is divided by septa into 250 lobules → 800 seminiferous tubules
Each tubule is ~31inches → each testis has ~0.5 mile of tubules

Question 4

Scrotum

Answer 4

Fleshy pouch that holds the testes
consists of a thin layer of skin containing smooth muscle
muscle contracts and relaxes in response to temperature and other stimuli

Question 5

Epididymis

Answer 5

Beginning of male reproductive tract
Where sperm reach maturity
Contains a coiled tube about 20 feet long

Question 6

Vas deferens (or ductus deferens)

Answer 6

Stores matured sperm cells
Connects epididymis to ejaculatory duct
Peristaltic contractions move spermatozoa and fluid down the duct
Can store spermatozoa for up to several months in suspended animation

Question 7

Seminal Vesicles

Answer 7

Contains:
Fructose: feeds spermatozoa
Prostaglandins: causes smooth muscle contractions along male and female repro tracts
Fibrinogen: creates temporary sperm clot or “plug” within vagina
60% of the volume of semen

Question 8

Cowper’s glands (bulbourethral glands)

Answer 8

Adds a lubricating substance
Also secretes thick, sticky alkaline mucus to neutralize urinary acids in the urethra

Question 9

Urethra

Answer 9

Semen AND urine exit out of the urethra

Question 10

Penis

Answer 10

organ that passes urine and semen through the urethra to the outside
3 regions:
Root: attaches penis to body
Body (shaft): contains erectile tissue
Glans: surrounds external urethral opening

Question 11

Erectile Tissue

Answer 11

Body has 3 columns of erectile tissue
2 corpus cavernosa: extends as far as the glans
1 corpus spongiosum: Extends all the way to the tip; makes the glans stiff; surrounds urethra

Question 12

Erection

Answer 12

when the penis fills with blood and gets stiff; makes it so that the penis can go into the vagina

Question 13

Emission

Answer 13

sperm move from testes → epididymis → urethra

Question 14

Ejaculation

Answer 14

skeletal muscles at the base of the penis contract, increasing pressure in the erectile tissue, expelling semen

Question 15

Circumcision

Answer 15

Procedure where the foreskin is surgically removed
Parents typically choose circumcision based on religious, social, or cultural reasons; some have concerns about hygiene

Question 16

Vasectomy

Answer 16

Medical procedure where the vas deferens is cut and sealed off to prevent sperm from entering semen (ejaculate)