Topic H - Human Reproduction Flashcards
definition of sexual reproduction
involves fusion of 2 cells called gametes, which are made of 2 types, male ( sperm ) + (egg)
therefore requires 2 parents male + female
definition of asexual reproduction
offspring are genetically identical to parent because simply gets a copy of parents
only requires 1 parent
what is the function of the male reproductive system
produce sperm ( male gametes ) deposit sperm in the vagina
what is the function of the female reproductive system
produce ova (female gametes ) nurture + protect the developing embryo/foetus
where specifically are sperm produced
in the testes by mesiosis
how does the sperm adapt to its requirement ( what are the requirements )
need to be at low temperature so the testes hang outside the body in the scrotum ( ball sack )
how are the prostate gland and seminal vesicle adapted for the sperm
they produce a liquid called seminal fluid (contains nutrients for energy) in which the sperm are able to swim.
what is seminal fluid and sperm together both known as
semen
when are sperm released
when a man ejaculates
how does the egg prevent more than one sperm entering
release chemicals which alter the cell membrane making it impenetrable for the sperm
which female structure filters out only the healthy sperm
cervix
what is the role of progesterone in the menstrual cycle
starts being produced at ovulation
maintains uterus lining by thickening it
prepares the body for pregnancy
what is the role of oestrogen in the menstrual cycle
repairs uterus lining
high levels stimulate the release of LH=ovulation
PAPER 2
what is the role of FSH in the menstrual cycle
cause the development of the follicle which contains the ovum ( egg )
PAPER 2
what is the role of LH in the menstrual cycle
cause ovulation ( release of egg) cause the formation of the corpus luteum
what is the role of the plancenta
allows constant exchange of materials between mother and foetus ( both nurtients and waste ) eg. oxygen, urea ,glucose, lipids, amino acids, nerals vitamins, co2
what does the placenta contain
both the blood vessels of the mother and foetus
what do the blood vessels in the placenta do
they run very close to each other but do not mix ( mother will recognise foetus blood as foreign and will attack it as a virus )
how do substances move between mothers blood and foetus’ s blood
by diffusion
what essential substances does the foetus need from the mother which it gets through diffusion through the placenta
eg. oxygen, urea ,glucose, lipids, amino acids, minerals vitamins, co2
where do the waste products of foetus go
back into mother blood so mother can excrete substance such co2 + urea which the foetus can not do itself
what is the embryo protected by
amniotic fluid
explain the process fertilisation
involves the fusion of male and female gamete ( egg + sperm ) = zygote = cell division = embryo= cell division = foetus ( child )
what is the role oestrogen ( female ) in the development of 2nd sexual characteristics
breast development
hair growth
hips widen
menstruation begins
what is the role testosterone ( male ) in the development of 2nd sexual characteristics
voice change
muscle developments
hair growth
producing gametes ( sperm)
where is oestrogen and progesterone found
ovaries
definition of menstruation
shedding of uterus lining
what day does ovulation occur
day 14
what is the order of menstrual cycle
menstruation
implantation
ovulation
fertilisation
