Human Bio: Reproductive System and
cell division ATAR 11 Exam
Fertilisation
Gonads
Gametes - Correct Answers -F: joining of the male and female sex cells to produce a
single cell called a zygote.
G: primary sex organs (Testes, ovaries)
Ga: Organism's reproductive cells (sperm and ovum)
Male reproductive system: Testes - Correct Answers -- Gonads: 2 testes which
produces the gametes (sperm). Testes are supported by scrotum (skin-covered pouch,
internally divided into 2 sacs, containing a testis.)
- Requires a temp 2 C lower than the normal body temp. They lie on the outside of the
body in the scrotum. Wall of scrotum has smooth muscle fibres, which can contract to
move it closer to body (slightly higher temp), or can relax to move away from body
(cooler).
embryonic membranes - Correct Answers -- Amnion: first membrane to develop. by day
8, surrounds embryo enclosing a cavity where it secretes amniotic fluid. fluid protects
embryo against physical injury (shock absorber). also maintains constant temp and
allows developing embryo/foetus to move freely. expands as growth occurs and
ruptures before childbirth, releasing the fluid (breaking of waters)
- Chorion: formed by outer cells of blastocyst and a layer of mesodermal cells.
surrounds embryo and other three embryonic membranes. as amnion enlarges, if fuses
with inner layer of chorion and eventually becomes main part of foetal portion of
placenta.
- Yolk sac and allantois: not as important in humans as other animals. form outer
structure of umbilical chord.
Roles of the placenta - Correct Answers -- Endocrine: secretes hormones necessary for
pregnancy
- Excretory: transports nitrogenous wastes like urea, ammonia from foetal blood to
mother's blood supply for excretion by her kidneys.
- Immune: transports antibodies from mother into foetal blood supply so it has immunity
to some infectious diseases.
- Nutritional: Transports nutrients like glucose, amino, fatty acids, vitamins etc. from
mother's to foetal blood; stores some essential nutrients early in prego and releases
them later when demand is greater.
- Respiratory: Transports oxygen from mother to foetus and co2from foetus to the
mother.
, Production of sperm - Correct Answers -- Testes are oval shape (4.5cm long, 2.5cm
wide and 3cm thick). Internally divided into between 200-300 lobules (compartments)
filled with seminiferous tubules (fine tubules) which are lined with sperm-producing cells.
The tubules in each compartment join to form a short, straight tubule, which join forming
a duct.
- This leaves the testis into epididymis. (interstiaial cellsare between seminiferous
tubules and secrete testosterone hormone)
Epididymis
Vas deferens
Tranfer of contents - Correct Answers -- E: highly folded tubule that fits against rear
surface of each testis. Sperm from testes enter and are stored in here for a month while
they mature.
- VD: The tubule of the epididymis continues to become a vas deferens (sperm duct),
carries sperm away from testis. Extends upward, passes into abdominal cavity and
crosses upper surface of the bladder, then turns downwards, looping into the bladder.
under the bladder, both vas deferens join urethra, which runs urine and semen through
penis to exterior.
to transfer into a female, sperm must be in liquid form (semen), nourishes and aids
transport of sperm and is a mixture of secretions from glands (seminal vesicles, prostate
and bulbourethral gland).
3 Glands in male reproductive system - Correct Answers -+ Seminal Vesicles: pair of
pouch-like organs about 5cm long located behind urinary bladder. secretes a thick fluid
rich in sugars and makes up 50% of the volume of semen.
+ Prostate Gland: where both vasa deferentia join urethra. Single gland, doughnut
shaped surrounds urethra below the bladder. Secretes a thin, milky alkaline fluid that is
part of the semen.
+ Bulbo- Urethral Glands: (Cowper's glands) 2 small pea sized glands. Below prostate,
on either side of urethra. secretes clear mucus, carried to urethra by a duct from each
gland. acts as a lubricant but most precedes emission of seminal fluid, so only a small
amt is inc. in semen.
erectile tissue - Correct Answers -connective tissue with rich blood supply. has a large
no. of sponge like spaces, which fill with blood during sexual arousal. causes penis to
enlarge, stiffen and become erect. only when penis is erect can it successfully enter the
vagina.
Female reproductive system: ovaries - Correct Answers -- gonads are the 2 ovaries.
Produce female gametes. 3cm long almond shaped. Located within body unlike testes.
each in abdominal cavity.
- composed of a mass of connective tissue called the stroma, which is surrounded by a
layer of cells containing numerous germ cells. Each germ cell enclosed in a follicle.
Many are in diff stages of development. when mature, moves to ovary surface and
ruptures and enters into fallopian tube.
cell division ATAR 11 Exam
Fertilisation
Gonads
Gametes - Correct Answers -F: joining of the male and female sex cells to produce a
single cell called a zygote.
G: primary sex organs (Testes, ovaries)
Ga: Organism's reproductive cells (sperm and ovum)
Male reproductive system: Testes - Correct Answers -- Gonads: 2 testes which
produces the gametes (sperm). Testes are supported by scrotum (skin-covered pouch,
internally divided into 2 sacs, containing a testis.)
- Requires a temp 2 C lower than the normal body temp. They lie on the outside of the
body in the scrotum. Wall of scrotum has smooth muscle fibres, which can contract to
move it closer to body (slightly higher temp), or can relax to move away from body
(cooler).
embryonic membranes - Correct Answers -- Amnion: first membrane to develop. by day
8, surrounds embryo enclosing a cavity where it secretes amniotic fluid. fluid protects
embryo against physical injury (shock absorber). also maintains constant temp and
allows developing embryo/foetus to move freely. expands as growth occurs and
ruptures before childbirth, releasing the fluid (breaking of waters)
- Chorion: formed by outer cells of blastocyst and a layer of mesodermal cells.
surrounds embryo and other three embryonic membranes. as amnion enlarges, if fuses
with inner layer of chorion and eventually becomes main part of foetal portion of
placenta.
- Yolk sac and allantois: not as important in humans as other animals. form outer
structure of umbilical chord.
Roles of the placenta - Correct Answers -- Endocrine: secretes hormones necessary for
pregnancy
- Excretory: transports nitrogenous wastes like urea, ammonia from foetal blood to
mother's blood supply for excretion by her kidneys.
- Immune: transports antibodies from mother into foetal blood supply so it has immunity
to some infectious diseases.
- Nutritional: Transports nutrients like glucose, amino, fatty acids, vitamins etc. from
mother's to foetal blood; stores some essential nutrients early in prego and releases
them later when demand is greater.
- Respiratory: Transports oxygen from mother to foetus and co2from foetus to the
mother.
, Production of sperm - Correct Answers -- Testes are oval shape (4.5cm long, 2.5cm
wide and 3cm thick). Internally divided into between 200-300 lobules (compartments)
filled with seminiferous tubules (fine tubules) which are lined with sperm-producing cells.
The tubules in each compartment join to form a short, straight tubule, which join forming
a duct.
- This leaves the testis into epididymis. (interstiaial cellsare between seminiferous
tubules and secrete testosterone hormone)
Epididymis
Vas deferens
Tranfer of contents - Correct Answers -- E: highly folded tubule that fits against rear
surface of each testis. Sperm from testes enter and are stored in here for a month while
they mature.
- VD: The tubule of the epididymis continues to become a vas deferens (sperm duct),
carries sperm away from testis. Extends upward, passes into abdominal cavity and
crosses upper surface of the bladder, then turns downwards, looping into the bladder.
under the bladder, both vas deferens join urethra, which runs urine and semen through
penis to exterior.
to transfer into a female, sperm must be in liquid form (semen), nourishes and aids
transport of sperm and is a mixture of secretions from glands (seminal vesicles, prostate
and bulbourethral gland).
3 Glands in male reproductive system - Correct Answers -+ Seminal Vesicles: pair of
pouch-like organs about 5cm long located behind urinary bladder. secretes a thick fluid
rich in sugars and makes up 50% of the volume of semen.
+ Prostate Gland: where both vasa deferentia join urethra. Single gland, doughnut
shaped surrounds urethra below the bladder. Secretes a thin, milky alkaline fluid that is
part of the semen.
+ Bulbo- Urethral Glands: (Cowper's glands) 2 small pea sized glands. Below prostate,
on either side of urethra. secretes clear mucus, carried to urethra by a duct from each
gland. acts as a lubricant but most precedes emission of seminal fluid, so only a small
amt is inc. in semen.
erectile tissue - Correct Answers -connective tissue with rich blood supply. has a large
no. of sponge like spaces, which fill with blood during sexual arousal. causes penis to
enlarge, stiffen and become erect. only when penis is erect can it successfully enter the
vagina.
Female reproductive system: ovaries - Correct Answers -- gonads are the 2 ovaries.
Produce female gametes. 3cm long almond shaped. Located within body unlike testes.
each in abdominal cavity.
- composed of a mass of connective tissue called the stroma, which is surrounded by a
layer of cells containing numerous germ cells. Each germ cell enclosed in a follicle.
Many are in diff stages of development. when mature, moves to ovary surface and
ruptures and enters into fallopian tube.
