Hormones Flashcards
What are hormones?
They are chemical messagers sent through the blood and they are carried to specific cells in particular organs (target organs)
What are the hormones produced in?
They are produced in (and secreted by) various glands, they are called endocrine glands.
What are the 6 endocrine glands?
- pituitary gland -> it produces hormones that act on other hormones
- thyroid gland -> it produces thyroxine.
- ovaries-> it produces oestrogen (women)
- testes-> it produces testosterone (men)
- adrenal gland-> it produces adrenaline
- the pancreas-> it produces insulin
Neurones vs hormones
Neurones are a very fast action that has a short time acting on a precise area whereas hormones are released slower that has a long time acting on a general way.
What is Adrenaline?
Adrenaline is a hormone released by the adrenal glands and prepares the body fight or flight. It does this by activating processes that increase the supply of oxygen and glucose to cells
How is your body affected by negative feedback?
Your body can control the levels of hormones (and other substances) in the blood using negative feedback systems. When the body detects that level of a substance has gone above or below the normal level.
What is thyroxine?
Thyroxine is a hormone released by the thyroid gland, its plays an important role in regulating metabolic rate.
How is the menstrual cycle relates to hormones?
The hormones trigger different stages in the menstrual cycle, there are 4 hormones
- FSH>cause follicle to mature in one of the ovaries
- Oestrogen>causes the lining to thicken and grow
- LH>causes stimulation at day 14 making the egg to release
- Progesterone>causes the maintenance of the lining of the uterus
How can hormones be used to treat infertility?
There are two types of ways:
- Clomifene therapy - this works by causing more FSH and LH To be released which stimulates egg maturation and ovulation.
- IVF -they use these to grow embryos, once they are tiny balls of cells, they are transferred to the woman’s uterus to improve the chance of pregnancy.
How are hormones used to prevent pregnancy?
Hormones can be used for contraceptives, too much oestrogen meaning that egg development and production stop. Whereas progesterone can produce thick cervical mucus which prevents any sperm getting through.
Hormonal contraceptive methods pros and cons
-it is more effective at preventing pregnancy however there is some side effects of acne and mood changes also doesn’t protect from stis
What is homeostasis?
Is maintaining a constant internal environment, having the conditions is essential as it needs to function correctly.
Examples:
Osmoregulation-> you need to balance between the water you gain and lose
How do glucagon and insulin control blood glucose?
If blood glucose concentration is too high insulin is added which moves the glucose into the liver and muscle cells whereas if it is too low glucagon is added so it can increase the glucose in the blood stream.
