reproduction in human Flashcards
define reproduction
fusion of male gamete cells with female gamete cells to produce biologically non-identical zygote
where are egg cells made
ovaries
where are sperm cells made
testes
what is the role of sperm duct
transfers sperm cells from testis and urine to penis
what is the role of oviduct
transfers egg cells to the uterus
what is the role of prostate gland
produces semen fluid for sperm to swim in
define ovulation
egg matures and travels from ovary to oviduct
how does sperm cells and egg cells divide
by meiosis
how does egg cells travel from oviduct to uterus
cilia hair sweep it along and muscles in uterus lining wall move it by peristalsis
define ejaculation
sperm cells leaving the penis into the vagina
define fertilisation
the fusion of the nuclei of male and female gamete cells
state 3 adapting characteristics of egg cells
- layer of jelly hardens as soon as fertilisation with a sperm cell takes place to prevent any further fertilisation of another sperm cell
- cytoplasm contains an energy store to support a growing embryo
- nucleus contains chromosomes for fusion with sperm cells
state 4 adapting characteristics of sperm cells
- flagellum tail helps cell to move
- acrosome contains a lot of enzymes that help it dissolve the jelly surrounding egg cell for fusion
- middle piece contains mitochondria to release energy for movement
- nucleus contains chromosomes for fusion with egg cell
how does zygote divide
by mitosis
state the obvious difference between mitosis and meiosis
mitosis divides to produce identical cells
meiosis divides to produce non identical cells
state the order of a growing baby in the mother
zygote -> embryo -> fetus
where is the site of fertilisation
oviduct of the mother
where is the site of implantation
uterus lining
what is the role of placenta
allows exchange of substances from the mother’s blood to the baby’s and prevents any mixing between them
where is the placenta
walls of the uterus
what is the role of the umbilical cord
transports blood and other substances from the baby to the mother and vice versa
how is oxygen, amino acid and glucose is transferred from the mother to her fetus
by diffusion from the maternal’s blood to the baby’s
how is carbon dioxide, urine and toxins transferred from the fetus to the mother
by diffusion from the baby’s blood to the maternal
what is the membrane surrounding the fetus called and what is its function
it is the amnion, it releases amniotic sac which supports and protects the baby from bumping into the mother and prevents it from getting dry
list the stages of birth in order
- Amniotic sac breaks
- Muscles in the uterus wall contract
- Cervix dilates (gets wider)
- Baby passes out through the vagina
- Umbilical cord is tied and cut
- Afterbirth is delivered
state 4 points of what a pregnant woman should include in her diet + give reasons for each point
- calcium - growing bones of fetus
- iron - producing haemoglobin in rbcs of fetus
- extra carbs - needs more energy to move due to the presence of fetus inside her
- extra protein - to develop cells for the growing fetus
state 3 points of what a pregnant women should avoid doing + give reasons for each point
- smoking - carbon monoxide and nicotine can diffuse into the fetus’ blood which can cause slow growth or low birth weight
- drinking alcohol - also diffuses to the fetus blood and can cause brain damage
- prevent catching some illnesses like rubella - also diffuses to the fetus blood
what are the advantages and disadvantages of breast-feeding
\+ 1. mother-baby bond 2. transfers antibodies to the baby 3. consists of the exact right amount of nutrients for each growing stage of the baby 4. its free - mother does not have time for herself it is painful for the mother
what are the advantages and disadvantages of bottle-feeding
+
1. anyone can feed the baby, allows father-baby bond
2. mother has more time for herself
-
1. if equipments are not sterilised carefully, it’s easy for the baby to get infected
2. it’s expensive
list the order of stages of menstrual cycle
- walls of uterus thickens
- egg matured and released to oviduct
- by the time the egg reaches the uterus and it is not fertilised it is lost through the vagina along with uterus lining as it is no longer needed
- uterus lining begins to build up again for the next month period
state 3 secondary sexual characteristics of a boy
- facial hair and pubic grows
- voice breaks
- muscles develop
state 3 secondary sexual characteristics of a girl
- pubic hair grows
- breasts develop
- hip widens
what is the male sex hormone called + where is it made
testosterone, in testes
what is the female sex hormone called + where is it made
oestrogen, in ovaries
where is progesterone produced
ovaries
where is FSH and LH produced
pituitary gland
what are the roles of FSH and LH
secrete oestrogen to keep the uterus lining thick
what is the role of oestrogen
thickens the walls of uterus
state the order of release fo the 4 hormones in women
- follicle is developed inside ovaries
- follicle stimulates production of FSH
- follicle secretes oestrogen
- when follicle grows completely, LH is secreted (ovulation takes place)
- follicle stops secreting oestrogen and turns to a corpus luteum
- corpus luteum secretes progesterone instead
- FSH and LH stops secreting
what is the role of progesterone
maintains thick walls of uterus
