Topic 7 - Hormones, Fertility and Homeostasis Flashcards
Role of glucagon in blood glucose control?
If the blood glucose levels are too low, glucagon is added and it makes the liver turn glycogen into glucose. Glucose is then released into the blood by the liver and blood glucose increases.
How do hormonal contraception methods prevent pregnancy?
The pill or implant placed under the skin releases hormones to prevent ovulation and thicken cervix mucus, making it difficult for sperm to pass through.
Role of FSH in the menstrual cycle?
Causes a follicle to mature in one of the ovaries.
Stimulates oestrogen production.
Gland that FSH is released from?
Pituitary gland
Role of progesterone in the menstrual cycle?
Inhibits the release of LH and FSH.
Maintains uterus lining.
When the level of progesterone falls and there’s a low oestrogen level, the uterus lining breaks down.
A low progesterone level allows FSH to increase and the cycle starts again.
Gland that progesterone is released from?
Corpus luteum (after ovulation)
Define homeostasis.
The maintenance of a constant internal environment.
Role of oestrogen in the menstrual cycle?
Causes the uterus lining to thicken. A high level also stimulates an LH surge.
Gland that oestrogen is released from?
Ovaries
Where are hormones produced?
They are produced and secreted in/by endocrine glands..
How are hormones transported?
They are transported in the bloodstream.
Which gland releases LH?
Pituitary gland
Which 2 hormones are inhibited by increasing progesterone levels?
LH and FSH
Define osmoregulation.
The control of the balance of water and mineral salts in the body.
Which 3 hormones control metabolic rate?
Thyroxine, TSH, TRH
2 barrier methods for contraception?
- condoms
- female condom/femidom
- cervical cap
- diaphragm
Role of LH in the menstrual cycle?
Stimulates ovulation at day 14, meaning the follicle ruptures and the egg is released. It also stimulates the remains of the follicle to develop into a corpus luteum, secreting progesterone.
What is the effect of adrenaline on the body?
Adrenaline prepares the body in the face of threat:
It binds to specific receptors in the heart, causing the muscles to contract more frequently and with more force.
Blood pressure increases and blood flow to muscles is increased. This means that cells receive more oxygen and glucose for increased respiration. Adrenaline also binds to receptors in the liver, causing the liver to break down glycogen stores to release glucose. Blood glucose levels increase and more glucose transports to cells.
Cause of type 2 diabetes?
Pancreas doesn’t produce enough insulin or has become resistant to insulin. (Usually due to an unhealthy diet/lifestyle)
How is type 2 diabetes controlled?
Eating a healthy diet, regular exercise and losing weight.