Taneil Thompson
Human Reproduction
PLEASE NOTE THAT I HAVE SIFTED THROUGH THE IEB FINAL PAPERS
FROM 2011 TO 2018 AND ADDED SOME INFORMATION THAT KEPT
COMING UP. THIS INFORMATION IS IN PINK. I HAVE ALSO CHECKED
THROUGH THE SAGS DOCUMENT TO MAKE SURE THAT ALL THE
RELEVANT INFORMATION IS HERE. J
Male Reproductive System (see diagram on Page 3)
1. Scrotum:
• Contains and protects testis
• Acts as temperature regulator, testis 2-3C lower than body
(necessary for formation of fertile sperm)
2. Testes:
- Secrete testosterone, leads to rapid physical growth in puberty;
development of secondary sexual characteristics; regulate secretion
of LH and FSH; sex drive; sperm production.
• Two oval structures, suspended outside body
• Embryonic stage, testis in abdominal cavity below kidneys, descend
into scrotum before birth.
• Contain lobules that have highly convoluted tubules (seminiferous
tubules) lined by germinal epithelium. 250 meters per teste
• Between tubules, endocrine cells called interstitial cells/ cells of
Leydig.
• Produce sperm (male gametes) by germinal layer and testosterone
(male hormone) by interstitial cells.
3. Ducts:
a. Epididymis- seminiferous tubules join for 5m. immature sperm enter
epididymis to mature and to be stored for months.
b. Vas Deferens (Sperm Duct)- continuation of epididymis, leaves
scrotum, passes through prostate gland and enters urethra. Pushes
mature sperm forward using strong peristaltic (smooth muscles
contracts) waves known as ejaculation.
c. urethra- duct at end of uro-genital system leading to outside. Forms
common duct for transportation of sperm and urine.
SAHETI School, 2019 1
, Taneil Thompson
4. Prostate Gland:
• Plum-sized gland surround urethra at base of bladder
• Secretes fluid that aids in transport of sperm and contains enzymes
to make sperm more active.
• Fluid makes up one third of seminal fluid (semen)
5. Penis:
Three sections of erectile tissue (special spongy tissue). Two on dorsal
side (corpus cavernosa) one on ventral side (corpus spongiosum): dilation
of dorsal and central arteries supplying blood to penis. More blood fills
erectile tissue causing lengthening and stiffening called an erection. (WHY
ARE BLOOD VESSELS NEEDED? They allow for erection of penis, which
enables sperm to be placed deep inside female body increasing chances
of successful fertilisation.)
• Deposits semen with sperm into female vagina curing copulation.
• Only penis with no erectile bone (baculum), relies entirely on
engorgement (filling up) with blood.
• Not attached to abdominal wall, hangs free. Other mammals have a
penis that is stored internally until erect.
6. Semen (seminal fluid):
- includes male gametes and fluids released into the sperm ducts
along the way
- Consists of sperm (testis) and seminal fluid (vas deferens and
prostate)
- Average amount is 2.5 to 5 milliliters.
- Average number of sperm= 700million per ejaculation
- Infertile= semen with less than 20 million per ml
SAHETI School, 2019 2
Human Reproduction
PLEASE NOTE THAT I HAVE SIFTED THROUGH THE IEB FINAL PAPERS
FROM 2011 TO 2018 AND ADDED SOME INFORMATION THAT KEPT
COMING UP. THIS INFORMATION IS IN PINK. I HAVE ALSO CHECKED
THROUGH THE SAGS DOCUMENT TO MAKE SURE THAT ALL THE
RELEVANT INFORMATION IS HERE. J
Male Reproductive System (see diagram on Page 3)
1. Scrotum:
• Contains and protects testis
• Acts as temperature regulator, testis 2-3C lower than body
(necessary for formation of fertile sperm)
2. Testes:
- Secrete testosterone, leads to rapid physical growth in puberty;
development of secondary sexual characteristics; regulate secretion
of LH and FSH; sex drive; sperm production.
• Two oval structures, suspended outside body
• Embryonic stage, testis in abdominal cavity below kidneys, descend
into scrotum before birth.
• Contain lobules that have highly convoluted tubules (seminiferous
tubules) lined by germinal epithelium. 250 meters per teste
• Between tubules, endocrine cells called interstitial cells/ cells of
Leydig.
• Produce sperm (male gametes) by germinal layer and testosterone
(male hormone) by interstitial cells.
3. Ducts:
a. Epididymis- seminiferous tubules join for 5m. immature sperm enter
epididymis to mature and to be stored for months.
b. Vas Deferens (Sperm Duct)- continuation of epididymis, leaves
scrotum, passes through prostate gland and enters urethra. Pushes
mature sperm forward using strong peristaltic (smooth muscles
contracts) waves known as ejaculation.
c. urethra- duct at end of uro-genital system leading to outside. Forms
common duct for transportation of sperm and urine.
SAHETI School, 2019 1
, Taneil Thompson
4. Prostate Gland:
• Plum-sized gland surround urethra at base of bladder
• Secretes fluid that aids in transport of sperm and contains enzymes
to make sperm more active.
• Fluid makes up one third of seminal fluid (semen)
5. Penis:
Three sections of erectile tissue (special spongy tissue). Two on dorsal
side (corpus cavernosa) one on ventral side (corpus spongiosum): dilation
of dorsal and central arteries supplying blood to penis. More blood fills
erectile tissue causing lengthening and stiffening called an erection. (WHY
ARE BLOOD VESSELS NEEDED? They allow for erection of penis, which
enables sperm to be placed deep inside female body increasing chances
of successful fertilisation.)
• Deposits semen with sperm into female vagina curing copulation.
• Only penis with no erectile bone (baculum), relies entirely on
engorgement (filling up) with blood.
• Not attached to abdominal wall, hangs free. Other mammals have a
penis that is stored internally until erect.
6. Semen (seminal fluid):
- includes male gametes and fluids released into the sperm ducts
along the way
- Consists of sperm (testis) and seminal fluid (vas deferens and
prostate)
- Average amount is 2.5 to 5 milliliters.
- Average number of sperm= 700million per ejaculation
- Infertile= semen with less than 20 million per ml
SAHETI School, 2019 2
