Science Quiz -
Biology - Fertility (AQA) (Answers)
In GCSE Science students will be taught about how organisms use nerves and hormones. This is the fourth of five quizzes on that topic and it looks in particular at the effect that hormones have in human fertility.
There are several chemical substances called hormones and they each have a different effect on us. Many processes within the human body are coordinated by hormones. They are secreted by glands and are usually transported to their target organs by the bloodstream.
Hormones regulate the functions of many organs and cells. For example, the monthly release of an egg from a woman’s ovaries and the changes in the thickness of the lining of her womb are controlled by hormones secreted by the pituitary gland and by the ovaries.
[readmore]Several hormones are involved in the menstrual cycle of a woman. Hormones are involved in promoting the release of an egg:
Human fertility is controlled by hormones. This means that knowledge of hormones can be used to decide to increase, or reduce, the chances of fertilisation and pregnancy. Some women have levels of FSH and LH that are too low to stimulate egg production. Giving them a 'fertility drug' has the effect of stimulating their eggs to mature. Oral contraceptives contain hormones (oestrogen and progesterone) that inhibit the production of FSH so that no eggs mature.
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You can find more about this topic by visiting BBC Bitesize - Hormones in human reproduction - AQA
There are a number of hormones secreted by the pituitary gland and the ovaries that control fertility and the menstrual cycle
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There are many different glands in the body, each producing specific hormones
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Aldosterone helps to regulate your blood pressure, the levels of sodium and potassium in your body and the amount of water retained in the blood
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The pituitary gland is a pea-sized structure located at the base of the brain. It produces a number of other hormones as well as FSH
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Oestrogen stops FSH being produced so that only one egg matures in a cycle. It also stimulates the release of LH which causes the mature egg to be released from the ovary into the uterus
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It maintains the lining of the uterus during the middle part of the menstrual cycle and during pregnancy
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Oral contraceptives contain oestrogen, or oestrogen and progesterone. There is also a chance of an increased risk of developing blood clots but on the plus side there is evidence of a decreased risk of developing cancer of the uterus or ovaries
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Some women have difficulty becoming pregnant because they don't produce enough FSH to allow their eggs to mature. This type of treatment increases the production of mature eggs and can lead to twins or triplets being expected. This brings its own complications and can lead to premature or underweight babies being born
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It is also used when women have difficulty becoming pregnant because they don't produce enough FSH to allow their eggs to mature. The egg is fertilised outside the woman's body and then implanted into her uterus
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FSH is the hormone that stimulates eggs to mature in the ovaries. Having more mature eggs to work with gives a better chance of IVF succeeding
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