Zusammenfassung der Ressource
Human Reproduction (IGCSE Biology)
- Male reproductive system
- Roles
- Produce male gametes, Spermatozoa
(Sperm for short)
- Produced in testes
- Deliver gametes to the 'site' of fertilisation
- Urogenital system
- Merged urinary and reproductive system in males (Ureter & Bladder)
- Penis becomes erect when spaces in structure fill with blood
- Sperm duct (vas deferens)
- Carries sperm from testis to urethra
- Prostate gland
- Helps produce seminal fluid (makes up
99.5% of semen, sperm make up the
other 0.5%)
- Urethra
- Carries semen from sperm duct to tip of penis
- Testis/Testicle
- Made up of many coiled tubes (like balls of
wool which produce sperm; cells between
tubes produce testosterone)
- Hormones
- Pituitary gland
- Produces hormones which affect
other (endocrine) organs
- (Endocrine= glands which secrete hormones or other products directly into the blood)
- One pituitary hormone stimulates
the testes to produce testosterone
- Testosterone circulates in blood & stimulates
secondary sex characteristics (characteristics that
appear during puberty)
- Facial hair develops, hair
develops on chest, under
armpits & pubic region
- Chest broadens, muscles become larger
- Voice becomes deeper (larynx
/voicebox changes in shape)
- Testes are stimulated to
begin production of sperm
- Penis becomes larger,
scrotum expands to
contain larger testes
- Behaviour
- Boys become more
aggressive & territorial &
attracted to girls
- (Chemical messengers which
are produced by glands to alter
the activity of one or more
specific target organs)
- Male gametes (sperm)
- Smaller than ova
(female gametes)
- Produced in huge numbers (300 000 000
per ejaculation)
- Mobile- can swim by beating the flagellum (tail)
- Fertilises female gamete (ovum)
- Female reproductive system
- Roles
- Produce female gametes, Ovum (Ova as plural)
- Recieve male gametes (spermatozoa) for fertilisation
- Provides a 'site' for fertilisation & for development of
zygote (cell that forms when a sperm fertilises an egg )
- Female gametes (ova)
- Produced one at a time (once monthly) by the two ovaries
- Ovum travels along oviduct (Fallopian tube) towards the uterus
- Fertilised whilst in oviduct/Fallopian tube
- Ectopic pregnancy
- When fertilised ovum is implanted in fallopian
tube (instead of traveling through the tube and
implanting in the uterus)
- Zygote grows & develops into baby in uterus
- Much larger than male gametes (sperm)
- Do not move, but have
large food store
- Urogenital system
- Urinary system
- Bladder (pushed to one side)
- Ureter
- Oviduct/Fallopian tube
- Carries ovum to uterus
- Fertilisation usually occurs
in first third of oviduct
- Uterus/womb
- Where fetus
develops
- During pregnancy, uterus
increases in volume from
10cm3 to 5dm3 (3 = cubed)
- Funnel of oviduct
- Collects ovum released from ovary
at ovulation
- Ovary
- Contains follicles which develop the ova
- Produces oestrogen and progesterone
- Muscular wall of uterus
- Lining of uterus
- Cervix (neck of uterus)
- Opening of vagina
- Vagina/birth canal
- Recieves penis during sexual intercourse
- 'Way out' for baby at birth
- Hormones
- Pituitary gland
- Produces hormones which
affect other (endocrine) organs
- (Endocrine= glands which secrete
hormones or other products directly
into the blood)
- One pituitary hormone stimulates
ovaries to produce oestrogen
- Oestrogen circulates in blood and &
stimulates secondary sex characteristics
(characteristics that appear during puberty)
- Breasts develop & increase in size
- Nipples become larger
- Hair develops in pubic
region & under armpits
- Hips become broader (pelvis
widens & fat is deposited)
- Vagina increases in size
- Puberty can be delayed in
extremely muscular girls
(e.g. gymnasts)
- Behaviour
- Girls become more maternal
(motherly) and attracted to boys
- (Chemical messengers which are produced by glands
to alter the activity of one or more specific target
organs)