B10/11 Flashcards
What is homeostaisis (definition)?
The regulation of the internal conditions of a cell or organism to maintain optimum conditions for functions, in response to internal and external conditions changing.
Examples of homeostasis
Maintaining
- body temperature
- blood glucose levels
- water content
Dufference between hormonal and nervous systems
Nervous system is used to quickly transmit pain signsls or messages from your eyes
(Short time, fast)
Hormone system is used to send a long lasting effect (eg adrenaline)
(Slower, long lasting)
Name some important glands of the endocrine system (label on good note)
Pituitary glands - The pituitary gland in the brain is a ‘master gland’ which secretes several hormones into the blood in response to body conditions. These hormones in turn act on other glands to stimulate other hormones to be released to bring about effects.
Ovaries - produces oestrogen 🔴
Testes - produce testosterone involved in puberty and sperm production 🔴
Thyroid - produces thyroxine involved in rate of motabalism, temperature and heart rate 🔴
Adrenal Glands - produces adrenaline 🔴
Pancreas - produces insulin which regulates blood glucose levels
What is a hormone?
A chemical molecule which regulates a process in the body
What happens when the blood glucose levels of a organism are too high or low? What is this called?
Negative feedback loop (to keep the levels in the blood steady)
If the blood glucose concentration is too high, the pancreas produces the hormone insulin that causes glucose to move from the blood into the cells. In liver and muscle cells excess glucose is converted to glycogen for storage..
Too low - a hormone called glucagon is secreted by the pancrease. The glucagon cause the glycogen to be converted into glucose and released into the blood
Describe the two types of diabetes
Type 1 - the pancreas produces little or no insulin. This means a high blood glucose level can kill them. These people need insulin therapy - involves several injections of insulin of insulin. People with type 1 need to think about regular exercise and limit intake of carbohydrate rich foods.
Type 2 - when a person becomes resistant to thier own insulin. This cause high blood sugar levels. Being overweight (obesity) can increase your chance of devloping type 2 diabetes. It can be controled by eating a carbohydrate controled deit and regular exercise.
Wgat is the endocrine system composed of, what does it do
Compare it to the nervois system
The endocrine system is composed of glands which secrete chemicals called hormones directly into the bloodstream. The blood carries the hormone to a target organ where it produces an effect. Compared to the nervous system the effects are slower but act for longer.
