CONTENT Flashcards
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What are hormones produced by?
Endocrine glands
How do hormones travel through the body?
via the bloodstream
What is the purpose of hormones?
They travel around their body until they reach their target organs. Each hormone causes its target organ(s) to respond, e.g. by releasing another chemical substance. Different hormones have different target organs and cause different substances.
From where are TRH and CRH secreted?
hypothalamus
From where is TSH secreted?
pituitary gland
From where is ADH secreted?
pituitary gland
From where are FSH and LH secreted?
pituitary gland
From where are insulin and glucagon secreted?
pancreas
From where is adrenalin secreted?
adrenal gland
From where are progesterone and oestrogen secreted?
ovaries
From where is testosterone secreted?
testes
From where is thyroxine secreted?
thyroid gland
What is the target organ of TRH and CRH?
pituitary gland
What is the target organ of TSH?
thyroid gland
What is the target organ of ADH?
kidney
What is the target organ of FSH and LH?
ovaries
What are the target organs of insulin and glucagon?
liver, muscles, adipose tissue
What are the target organs of adrenalin?
various organs e.g. heart, liver, blood vessels
What is the target organ of progesterone?
uterus
What are the target organs of oestrogen?
ovaries, uterus, pituitary gland
What are the target organs of testosterone?
male reproductive organs
What are the target organs of thyroxine?
all cells
What is adrenaline?
Adrenalin is a hormone that is released from the adrenal glands in response to sudden stress. It brings out the ‘fight or flight’ response
What does adrenalin do?
- increases heart rate
- constricts some blood vessels to make blood pressure higher
- dilates other blood vessels to increase blood flow to muscles
- causes the liver to convert glycogen to glucose, which is released into the blood
What is thyroxine?
Thyroxine is a hormone that controls metabolic rate. This is the rate at which the cells respire. It is measured as the rate energy transfers in the body. The production of thyroxine is an example of negative feedback.
How does thyroxine control metabolic rate?
When the concentration of thyroxine in the blood is too low, this stimulates a corrective mechanism. The hypothalamus secretes more TRH which causes the pituitary to produce more TSH. As a result, the thyroid produces more thyroxine. If the thyroxine concentration is too high, this inhibits TRH production by the hypothalamus, so less thyroxine is produced
What is menstruation?
Menstruation is the breakdown of the uterus lining
What happens during week 1 of the menstrual cycle?
The uterus lining breaks down, this usually lasts for the first 5 days of the menstrual cycle
What happens during week 2 of the menstrual cycle?
The lining of the uterus is gradually built up. Ovulation is the release of an egg from an ovary. This usually takes place around day 14
What happens between weeks 2-3 of the menstrual cycle?
Days 14-16 are the days when fertilisation is most likely to take place.
What happens to the uterus lining if fertilisation takes place?
If fertilisation occurs, the uterus lining remains thick so that the embryo can embed in the lining and obtain the nutrients that it needs.
What happens between weeks 3-4 of the menstrual cycle?
The lining of the uterus continues to build up
What happens during week 4 of the menstrual cycle?
If fertilisation takes place then the uterus lining is maintained and the breakdown does not happen
