homeostasis

Question 1

definition of homeostasis

Answer 1

maintenance of a constant internal environment to ensure that the conditions of blood and tissue fluid are kept within narrow limits

Question 2

parts of system of homeostatic control

Answer 2

normal (set point), stimulus, receptor, control centre, corrective mechanism, effector

Question 3

effect of insulin secretion

Answer 3

cell membranes become more permeable to glucose, causing more glucose to diffuse into liver and muscle cells. this stimulates the liver and muscle cells to convert excess glucose into glycogen for storage. blood glucose concentration decreases to normal

Question 4

what if too little insulin is secreted

Answer 4

blood glucose concentration will increase as glucose cannot be stored or utilised. muscle cells will have no glycogen reserves, causing body cells to grow weak and lose weight

Question 5

what if too much insulin is secreted

Answer 5

blood glucose concentration decreases, resulting in ‘shock’, seizures, fits or collapse

Question 6

effect of glucagon secretion

Answer 6

stimulates the conversion of glycogen into glucose. glucose enters bloodstream and blood glucose concentration increases to normal

Question 7

similarities between insulin and glucagon

Answer 7

1. both are secreted by the islets of langerhans in the pancreas
2. both are hormones that help to regulate the blood glucose concentration in the body

Question 8

risk factors of diabetes

Answer 8

obesity, age, family history, blood lipid levels, sedentary lifestyle