blood glucose concentration

Question 1

what is the homeostatic control of bgc?

Answer 1

1.regulation of blood glucose to maintain normal metabolic rates.
stimulus: increase/decrease in bgc
receptor: chemoreceptors for glucose in the pancreas
control centre: pancreas
effector: liver and body cells
response: increase/decrease in bgc

Question 2

what is insulin?

Answer 2

1. beta cells in the pancreas produce insulin.
2. reduces high blood glucose by stimulating the liver to absorb glucose and convert it into glycogen.
3. other body cells also have insulin receptors, in the presence of insulin these cells increase their uptake of glucose.

Question 3

what is glucagon?

Answer 3

1. alpha cells in the pancreas produce glucagon.
2. when glucagon binds to receptors on the liver cells, cells start to break down glycogen into glucose. the liver releases the glucose back into the blood, increasing the blood glucose levels.

Question 4

what are problems with glucose regulation?

Answer 4

1. hypoglycaemia- extremely low glucose and high insulin levels
2. hyperglycaemia- extremely high glucose levels
3. diabetes mellitus, affects regulation of blood glucose
   type 1: autoimmune disorder. the immune system attacks and destroy its own beta cells. people with type 1 diabtes cannot produce enough insulin to regulate blood glucose levels.
   type 2: can still produce insulin, however body is resistant to insulin. insulin receptors do not respond properly.

Question 5

Exam Q: A student is given a 5mg/L glucose rich drink 1 hour after waking up in the morning. The student has been asleep for 9 hours?
a) Describe the response that their body would have immediately after they have woken up.

Answer 5

1. low blood glucose concentration acts as a stimulus that is detected by chemoreceptors in the pancreas.
2. alpha cells of the pancreas produce glucagon in response to this stimulus which moves through the bloodstream to the target cells and organs such as the liver
3. the liver responds by converting glycogen into glucose, therefore increasing blood glucose levels straight after waking up

Question 6

b) Then describe the response their body would have 2 hours after the drink.

Answer 6

1. After the drink. high blood glucose concentration acts as a stimulus that is detected by the chemoreceptors in the pancreas
2. Beta cells of the pancreas produce insulin in response to this stimulus which moves through the bloodstream to target cells and organs like the liver and skeletal muscles
3. The liver and skeletal muscles respond by taking up glucose and converting it to glycogen, therefore decreasing blood glucose levels after the glucose rich drink

Question 7

c) another student drinks the same drink after waking up, but after 5 hours their blood glucose concentration is higher than when they first woke up. Explain why this student’s blood glucose concentration still remains high.

Answer 7

This student might have diabetes. This means that they cannot regulate their blood glucose levels. This is because their pancreas is not able to produce insulin or their body cannot respond to insulin. Therefore, their blood glucose conc. remains high.