menstrual cycle Flashcards
what is menstruation?
the breakdown of the uterus lining
what is menopause?
when the menstrual cycle stops
what is fertilisation?
fusing of male and female gametes
what is pregnancy?
when a fertilised egg develops in the womb
what is ovulation?
the release of an egg from the ovary
why does the menstruation cycle occur?
prepares the uterus lining so it can receive a fertilised egg.If the egg is unfertilised,it becomes lost in the breaking down of the uterus lining causing bleeding
what happens during the first 1-5 days?
uterus lining breaks and the unfertilised egg is lost
what happens during 6-12 days
egg cells mature in the ovaries and the lining is building up again
what happens in 14 days
ovulation
what happens in 16-28 days?
the lining thickens and if a fertilised egg does not implant itself onto the uterus lining then the cycle begins again
how do twins happen?
how do identical twins happen?
when two or more egg cells are released and become fertilised
when a single egg cell is released and splits into two
what does progesterone do?
maintains the uterus lining and stops the production of FSH and LH
what does oestrogen do
stimulates the release of LH and stops FSH,thickens uterus lining
what does the luteinising hormone do
-stimulates ovulation -the follicle ruptures and the egg is released
what does the FSH hormone do
stimulates oestrogen production
-causes an egg to mature
