paper 2 specification 4 Flashcards
what is homeostasis
-maintaining the right conditions in the body so that everything functions properly
- this is important because your cells need the right condition to function properly such as enzyme action
what are blood glucose regulation, osmoregulation and thermoregulation
-you need to make sure the amount of glucose in your blood doesn’t get too high or too low
-keep a balance of water you pee, sweat and breathe out and in
-reducing body temp when its hot and increasing when its cold
Explain how blood glucose concentration is regulated by glucagon
-eating foods containing carbs puts glucose in the blood from the small intestine
-normal metabolism of cells removes glucose
-exercise removes more glucose
-excess glucose is stored as glycogen in the liver and muscles
-when these stores are full then it is stored as lipid (fat) in tissues
-changes in blood glucose are monitored by the pancreas using hormone insulin and glucagon
how does INSULIN fix HIGH blood glucose lev
-insulin is secreted from the pancreas and enters the bloodstream to bind to receptors on liver and muscle cells which tells them to take in some glucose to combine it into glycogen-a long-term storage form of glucose)
blood glucose is then reduced
how does GLUCAGON fix LOW blood glucose levels
glucagon is secreted from the pancreas and not the bloodstream which then binds to liver cells to tell them to turn glycogen into glucose which is then released into the blood by the liver and blood glucose increases
Explain the cause of type 1 diabetes and how it is controlled
-where the pancreas produces no or little insulin this means the person’s blood glucose can rise and kill them
-will need to be treated with insulin therapy-injecting insulin into the subcutaneous tissue where it will enter the bloodstream.Done at mealtimes so that glucose is removed quickly once it has been digested. The amount of insulin injected depends on the diet and how active they are
what else do people with type 1 diabetes need t think about other than insulin therapy
-limiting the intake of simple carbs like sugars
-taking regular exercise to remove excess glucose
Explain the cause of type 2 diabetes and how it is controlled
when the pancreas doesn’t produce enough insulin or the person becomes insulin resistant
-leads to obesity BMI of over 30
-a waist-to-hip ratio of over 1.0 for men and 0.85 for women is abdominal obesity
-healthy diet, regular exercise and losing weight, Medication like insulin injections
Describe the need to transport substances into and out of a range of organisms, including oxygen, carbon dioxide, water, dissolved food molecules, mineral ions and urea
-cells need oxygen for respiration which produces C02 as a waste product. These two gases move between cells and the environment through diffusion
-water is taken up by cells by osmosis and dissolved food molecules and mineral ions diffuse along with it
-urea (waste product made by animals from proteins) diffuse from cells to the blood plasma for removal from the body by the kidneys
Explain how blood glucose concentration is regulated by glucagon
-eating foods containing carbs puts glucose in the blood from the small intestine
-normal metabolism of cells removes glucose
-exercise removes more glucose
-excess glucose is stored as glycogen in the liver and muscles
-when these stores are full then it is stored as lipid (fat) in tissues
-changes in blood glucose are monitored by the pancreas using the hormone insulin and glucagon
