Hormones in Humans: Reproduction & Metabolism Flashcards
All 23 cards in this deck
What is the main female reproductive hormone, and where is it produced?
Oestrogen, produced in the ovary.
What is the main male reproductive hormone, where is it produced, and what does it do?
Testosterone, produced by the testes; it stimulates sperm production and the male secondary sex characteristics at puberty.
What is the role of FSH (follicle stimulating hormone) in the menstrual cycle, and where is it produced?
It causes maturation of an egg in the ovary; it is produced by the pituitary gland.
What is the role of LH (luteinising hormone) in the menstrual cycle, and where is it produced?
It stimulates the release of the egg (ovulation); it is produced by the pituitary gland.
Which two hormones, both produced in the ovary, are involved in maintaining the lining of the uterus?
Oestrogen and progesterone.
True or false? On a graph of hormone levels in the menstrual cycle, the peak in LH at about day 14 is caused by a high level of oestrogen.
True. A high oestrogen level stimulates LH release, which triggers ovulation; oestrogen also inhibits FSH.
How do oral contraceptives (the pill) prevent pregnancy?
They contain hormones that inhibit FSH production, so no eggs mature.
Which hormone is given by injection, implant or skin patch as a contraceptive, and what does it do?
Slow release progesterone, which inhibits the maturation and release of eggs for a number of months or years.
How does an intrauterine device (IUD) prevent pregnancy?
It prevents the implantation of an embryo, or releases a hormone.
How do barrier methods of contraception work, and name two.
They prevent the sperm reaching an egg; e.g. condoms and diaphragms.
Name three non-hormonal methods of contraception other than barrier methods.
Spermicidal agents (kill or disable sperm), abstaining from intercourse when an egg may be in the oviduct, and surgical sterilisation of the male or female.
Which two hormones are given in a 'fertility drug', and why?
FSH and LH, to stimulate eggs to mature so the woman may become pregnant in the normal way.
In IVF, at what stage of development are embryos inserted into the mother's uterus, and how many?
When they are tiny balls of cells; one or two embryos are inserted.
Give three disadvantages of IVF treatment.
It is very emotionally and physically stressful, success rates are not high, and it can lead to multiple births which are a risk to both the babies and the mother.
True or false? In IVF the eggs are fertilised inside the mother's oviduct.
False. The eggs are collected from the mother and fertilised by the father's sperm in the laboratory.
True or false? A woman treated with a fertility drug containing FSH and LH may become pregnant in the normal way.
True. The hormones cause eggs to mature and be released, so fertilisation can happen inside her body.
Where is adrenaline produced, and when is it released?
By the adrenal glands, in times of fear or stress.
What are the effects of adrenaline in the body?
It increases the heart rate and boosts the delivery of oxygen and glucose to the brain and muscles, preparing the body for 'flight or fight'.
Where is thyroxine produced, and what does it do?
By the thyroid gland; it stimulates the basal metabolic rate and plays an important role in growth and development.
What is negative feedback in hormone control?
When the level of a substance rises above or falls below normal, a response is triggered that brings the level back to normal.
True or false? Adrenaline levels in the blood are controlled by negative feedback.
False. Thyroxine is controlled by negative feedback; adrenaline is released in response to fear or stress.
Give one advantage and one disadvantage of using the contraceptive pill rather than condoms.
Advantage: more effective at preventing pregnancy if taken correctly.
Disadvantage: can cause side effects and gives no protection against sexually transmitted infections.True or false? Sterilisation is a suitable method of contraception for a young woman who may want children in a few years' time.
False.
Sterilisation is permanent and very hard to reverse, so a reversible method such as the pill, implant or condoms would suit her better.