The human endocrine system 2.0 Flashcards
what does thyroxine do?
stimulates metabolic rate
how does thyroxine stimulate metabolic rate? (2)
-controls the speed at which oxygen and food products react
-to release energy for the body to use
what are the levels of thyroxine controlled by?
negative feedback
what do low levels of thyroxine in the bloodstream result in? (4)
-stimulate the hypothalamus to release TRH
-this causes the pituitary to release TSH
-so the thyroid releases more thyroxine.
-So blood levels return to normal.
what do normal levels of thyroxine in the bloodstream result in? (3)
- inhibit TRH release from the hypothalamus
- and the production of TSH by the pituitary,
-so normal blood levels are maintained.
what is the effect of adrenalin on the body? (2)
-increases breathing rate, heart rate (therefore blood flow) and blood pressure
-conversion of glycogen to glucose in liver cells, increasing blood glucose
what is adrenalin NOT controlled by?
negative feedback
why does adrenalin increase blood glucose? (2)
-more glucose being delivered to the muscles
-and more energy being released by respiration in the muscles.
what does insulin do?
regulates glucose concentrations in the blood.
what happens when the blood glucose concentration is too high? (3)
-pancreas produces the hormone insulin,
-this causes glucose to move from the blood into the cells.
what happens to liver and muscle cells when there is excess glucose?
glucose is converted to glycogen for storage, and will be used at a later date
what is the effect of low glucose on the:
-pancreas
-liver
-blood glucose level
-Insulin not secreted into the blood
-Does not convert glucose into glycogen
-Increases
what is the effect of high glucose on the:
-pancreas
-liver
-blood glucose level
-Insulin secreted into the blood
-Converts glucose into glycogen
-Decreases
what is diabetes?
a condition where the blood glucose levels cannot be controlled by the body
what happens in type 1 diabetes?
pancreas fails to produce enough insulin
what is type 1 diabetes characterised by?
how can it be controlled?
-uncontrolled high blood glucose levels
-injecting insulin
people with type 1 diabetes have to monitor their blood glucose levels throughout the day. what can they do to reduce the amount of injected insulin they need? (2)
-eat foods that will not cause large increases in blood sugar level
-exercising, which can lower blood glucose levels due to increased respiration in the muscles.
what happens in type 2 diabetes?
the person’s body cells no longer respond to insulin produced by the pancreas
how can type 2 diabetes be controlled? (2)
a carbohydrate controlled diet and an exercise regime
why do people with type 2 diabetes need to be under a carbohydrate based diet?
Carbohydrate is digested into glucose, which raises the overall blood glucose level
effect of blood glucose being too high on the:
-pancreas
-liver
-overall effect on glucose
-Insulin secreted into the blood
-Liver converts glucose into glycogen
-Goes down
effect of blood glucose being too low on the:
-pancreas
-liver
-overall effect on glucose
-Glucagon (not insulin) is secreted into the blood. -Liver does not convert glucose into glycogen. Glycogen is converted to glucose.
-Goes up
When blood sugar rises in the blood, insulin sends a signal to the liver, muscles and other cells to …(what)? (2)
to store the excess glucose.
-some is stored as body fat and other is stored as glycogen in the liver and muscles
If the blood glucose level is too low, the pancreas releases the hormone ______.
-what does it do?
glucagon
-travels to the liver in the blood and causes the break-down of glycogen into glucose
