What is the menstrual cycle?
The menstrual cycle is a recurring process in women which takes about 28 days.
What gland is FSH released by?
FSH is released by the pituitary gland.
Where are the eggs produced?
The eggs are produced in the ovaries.
What is the difference between sperm and egg production?
- Eggs are there since birth.
- Sperm are produced at puberty.
What is the uterus?
The uterus, known as the womb, is where the fertilised egg develops.
What is the cervix/the function?
- A ring of muscle at the lower end of uterus.
- Keeps the baby in place whilst pregnant.
What is menstruation?
Menstruation is the loss of blood and tissue from the lining of the uterus.
What does FSH do?
- Causes egg to mature in ovary follicle.
- Stimulates ovaries to release oestrogen.
What does oestrogen do?
- Stops production of FSH (only one egg matures.)
- Repairs/ thickens uterus
- Stimulates production of LH from pituitary gland
What does LH do?
- Triggers ovulation (to release the mature egg.)
Where is progesterone released from and what does it do?
- Produced in the ovaries: corpus luteum.
- Progesterone keeps the uterus thick for pregnancy.
- Stops production of FSH and LH.
What is the placenta?
The placenta is the organ that allows transfer of nutrients between the baby and mother.
What does the placenta produce if the woman is pregnant?
- The placenta produces progesterone if the woman is pregnant- maintains lining of uterus in pregnancy.
What happens to the progesterone levels when a woman has a period?
- The progesterone levels decrease.
What is the relation of oestrogen and progesterone?
- Oestrogen: thickens/ repairs the uterus lining.
- Progesterone: maintains this thick lining.
What happens on days 8-13 of the menstrual cycle?
- Progesterone levels rise.
- Uterus lining thickens.
On what day does ovulation take place?
Day 14.
What happens when a woman is given FSH and LH for in- vitro fertilisation?
- Her follicles will expand, eggs will mature.
- The mature egg will be released
Give step to step of IVF.
- Egg follicle maturation (stimulated by FSH.)
- Egg cells released and are taken from the ovaries.
- Sperm cells are taken from the man.
- Egg and sperm cells combine in a petri dish.
- One/ two healthy embryos are inserted into the uterus.
Why does IVF increase the chances of someone getting pregnant?
- IVF involves collecting eggs from woman’s ovaries by giving LH and FSH.
- The sperm cell then fuses with these collected ovaries in a petri dish, for fertilisation to occur.
- Then a few embryos are implanted in a uterus.
- This high level of hormones increases the chances of people coming pregnant.
- The fertilised cells are given time to develop.
- Several embryos are implanted.
Give three drawbacks of using hormones to increase fertility.
- The success rate of IVF is very low and very expensive.
- It can cause abdominal pain, dehydration, vomiting.
- Multiple unexpected births can happen at once.
What is the pituitary gland co-ordinated by?
Hypothalamus.
How do oral contraceptive pills work?
Contain oestrogen/ progesterone which inhibit the production of FSH for the eggs to mature.
Give two methods of contraception which form a physical barrier.
- Femi-dom, put into vagina. (stops sperm entering the body so protects against diseases.)
- Condom, put over penis to catch sperm (stops diseases being transmitted.)
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Communicable diseases10
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Energy in food7
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Drugs - effect on chemical reactions33
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Automatic Control Systems22
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Hormones Endocrine14
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Cell structure and microscopy31
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Cells26
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Digestive system60
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The respiratory system31
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Circulatory system25
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Immune system/ Infectious diseases48
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The menstrual cycle26
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Atoms and Elements79
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Photosynthesis and plant cells36
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Acid and Metal Reactions58
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Energy42
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Osmosis 115
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RP: Osmosis Practical27
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Active Transport: Oak National Academy6
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Diffusion: Oak National Academy18
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Working scientifically: Graphs7
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Group 1 elements17
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Group 7 elements17
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Group 0 elements6
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Gas collection methods3
