Menstrual Cycle Flashcards
The menstrual cycle is controlled by ___________
Hormones
How many hormones are involved in the menstrual cycle
4
Name the hormones involved in the menstrual cycle
FSH
Oestrogen
LH
Progesterone
FSH is released by the ___________
Pituitary
Oestrogen is released by the _____
_____
Ovaries
LH is released by the ___________
Pituitary
Progesterone is released by the ____________
Ovaries
What does FSH do
Makes ovaries mature an egg
What does Oestrogen do
Makes womb lining build up ready to receive egg
What does LH do
Makes ovaries release an egg
What does Progesterone do
Completes development of uterus lining
FSH makes the ovaries produce ___________
Oestrogen
Oestrogen makes the pituitary release ________
LH
LH triggers the release of ___________
Progesterone
Which hormones inhibit which hormones
FSH inhibits nothing
Oestrogen inhibits FSH
LH inhibits nothing
Progesterone inhibits FSH AND LH
If fertilisation doesn’t happen then what happens to the corpus luteum
It breaks down
What is the corpus luteum and what does it produce
A follicle that produces progesterone
If the corpus luteum breaks down then which hormone stops being released leading to FSH being released again
Progesterone
If fertilisation takes place : The corpus luteum won’t ________ ________, progesterone levels will stay ________ meaning that FSH is __________, the womb lining stays _________, the egg will __________ into the womb
Break down High Inhibited Thick Implant
Later in pregnancy the ____________ secretes progesterone
Placenta
What happens during week 1
Menstruation
What happens during week 2
The womb lining is repaired
What happens on day 14 (between weeks 2 and 3)
Ovulation
What happens during weeks 3 and 4
Womb lining is maintained
How long is the average menstrual cycle
28 days (4 weeks)
How long does menstruation last
5 days
How long can a sperm survive in the uterus for
Up to 3 days
How long does the egg (ovum) live for
About 36 hours
What does amniotic fluid do
The amnion membrane surrounds the embryo and is full of amniotic fluid which protects the baby from knocks and bumps
Which substances pass from the mother’s blood into the embryo’s blood via the placenta
Fatty acids + glycerol Water Oxygenated blood Glucose Amino acids
Which substances pass from the embryo’s blood into the mother’s blood via the placenta
Carbon dioxide
Urea
Deoxygenated blood
Why must the mother’s blood and the embryo’s blood not come into contact
They could have different blood types
How do substances pass between the mother and the baby
By diffusion through the placenta
The sperm cell will release ___________ to break down the ovum’s cell membrame
Enzymes
What is the stage between a fertilised egg cell and an embryo
A zygote
The pituitary gland releases oxytocin at 40 weeks which stimulates _________
Muscles in the uterus wall to contract
At birth the pituitary releases prolactin which stimulates what
The breasts to stimulate milk
What is ovulation
The release of an egg
What is the placenta
An organ which allows the blood of the embryo and mother to get very close to allow for the exchangeof useful substances
