The human endocrine system 2.0

Question 1

what does thyroxine do?

Answer 1

stimulates metabolic rate

Question 2

how does thyroxine stimulate metabolic rate? (2)

Answer 2

-controls the speed at which oxygen and food products react
-to release energy for the body to use

Question 3

what are the levels of thyroxine controlled by?

Answer 3

negative feedback

Question 4

what do low levels of thyroxine in the bloodstream result in? (4)

Answer 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.

Question 5

what do normal levels of thyroxine in the bloodstream result in? (3)

Answer 5

• inhibit TRH release from the hypothalamus
• and the production of TSH by the pituitary,
  -so normal blood levels are maintained.

Question 6

what is the effect of adrenalin on the body? (2)

Answer 6

-increases breathing rate, heart rate (therefore blood flow) and blood pressure
-conversion of glycogen to glucose in liver cells, increasing blood glucose

Question 7

what is adrenalin NOT controlled by?

Answer 7

negative feedback

Question 8

why does adrenalin increase blood glucose? (2)

Answer 8

-more glucose being delivered to the muscles
-and more energy being released by respiration in the muscles.

Question 9

what does insulin do?

Answer 9

regulates glucose concentrations in the blood.

Question 10

what happens when the blood glucose concentration is too high? (3)

Answer 10

-pancreas produces the hormone insulin,
-this causes glucose to move from the blood into the cells.

Question 11

what happens to liver and muscle cells when there is excess glucose?

Answer 11

glucose is converted to glycogen for storage, and will be used at a later date

Question 12

what is the effect of low glucose on the:
-pancreas
-liver
-blood glucose level

Answer 12

-Insulin not secreted into the blood
-Does not convert glucose into glycogen
-Increases

Question 13

what is the effect of high glucose on the:
-pancreas
-liver
-blood glucose level

Answer 13

-Insulin secreted into the blood
-Converts glucose into glycogen
-Decreases

Question 14

what is diabetes?

Answer 14

a condition where the blood glucose levels cannot be controlled by the body

Question 15

what happens in type 1 diabetes?

Answer 15

pancreas fails to produce enough insulin

Question 16

what is type 1 diabetes characterised by?
how can it be controlled?

Answer 16

-uncontrolled high blood glucose levels
-injecting insulin

Question 17

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)

Answer 17

-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.

Question 18

what happens in type 2 diabetes?

Answer 18

the person’s body cells no longer respond to insulin produced by the pancreas

Question 19

how can type 2 diabetes be controlled? (2)

Answer 19

a carbohydrate controlled diet and an exercise regime

Question 20

why do people with type 2 diabetes need to be under a carbohydrate based diet?

Answer 20

Carbohydrate is digested into glucose, which raises the overall blood glucose level

Question 21

effect of blood glucose being too high on the:
-pancreas
-liver
-overall effect on glucose

Answer 21

-Insulin secreted into the blood
-Liver converts glucose into glycogen
-Goes down

Question 22

effect of blood glucose being too low on the:
-pancreas
-liver
-overall effect on glucose

Answer 22

-Glucagon (not insulin) is secreted into the blood. -Liver does not convert glucose into glycogen. Glycogen is converted to glucose.
-Goes up

Question 23

When blood sugar rises in the blood, insulin sends a signal to the liver, muscles and other cells to …(what)? (2)

Answer 23

to store the excess glucose.
-some is stored as body fat and other is stored as glycogen in the liver and muscles

Question 24

If the blood glucose level is too low, the pancreas releases the hormone ______.
-what does it do?

Answer 24

glucagon
-travels to the liver in the blood and causes the break-down of glycogen into glucose