Hormonal coordination in humans (5.3) (M) Flashcards
What is a hormone?
A chemical messenger synthesised by an endocrine gland and released into the blood to affect specific target tissue
How does the endocrine system work?
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
Compare the effects of the nervous system with that of the endocrine system
Compared to the nervous system, the effects are slower, but act for longer
also via blood instead of electrical impulse
What is the pituitary gland referred to as?
the ‘master gland’
Where is the pituitary gland found?
the brain
Why is the pituitary gland called the master gland?
It 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.
Label these components on the body: pituitary gland, pancreas, thyroid, adrenal gland, ovary, testes.
- Ignore pineal gland, parathyroid gland*
- thyroid = thyroid gland*
What does the pancreas monitor and control in the human endocrine system?
blood glucose concentration
What does the pancreas (and liver/muscle cells) do if the blood glucose concentration is too high?
The pancreas detects high blood glucose
The pancreas produces the hormone insulin that causes glucose to move from the blood into the cells.
In liver and muscle cells, excess glucose to be converted to glycogen for storage.
What is type 1 diabetes?
a disorder in which the pancreas fails to produce sufficient insulin
often genetic
What is type 1 diabetes characterised by?
uncontrolled high blood glucose levels
How is type 1 diabetes normally treated?
with insulin injections
What is type 2 diabetes?
a disease in which the body cells no longer respond to insulin produced by the pancreas
not genetic
What are common treatments for type 2 diabetes?
a carbohydrate controlled diet and an exercise regime
What is a risk factor for type 2 diabetes?
obesity
What does the pancreas do if blood glucose concentration is too low?
pancreas detects low blood glucose
the pancreas produces the hormone glucagon that causes glycogen to be converted into glucose and released into the blood
Describe (via a diagram) how glucagon interacts with insulin in a negative feedback cycle to control blood glucose (sugar) levels in the body
What bodily fluids are lost during exhalation?
Water leaves the body via the lungs during exhalation
What bodily fluids are lost during sweating?
Water, ions and urea are lost from the skin in sweat.
There is (…) control over water, ion or urea loss by the lungs or skin.
no
What/how are bodily fluids lost in urine?
Excess water, ions and urea are removed via the kidneys in the urine.
What happens if there is a greater water concentration inside the cell after osmosis?
the cytoplasm pushes against the cell wall and becomes turgid