4.5.3.2 Control of Blood Glucose Concentration

Why does the concentration of glucose in the blood need to be kept within a certain limit?

Glucose is needed by cells for respiration

Where is blood glucose concentration controlled?

In the pancreas

What happens if glucose levels are too high?

The pancreas produces the hormone insulin which binds to the muscles and livers, causing the glucose to move from the blood into muscle cells for respiration and excess glucose to be converted into glycogen which is stored in the liver

What happens if someone does rigorous activity?

Glucose is used for respiration and therefore there’s less glucose in the blood

What happens if glucose levels decrease/are too low?

The pancreas produces the hormone glucagon, which binds to the liver cells and causes glycogen to break down into glucose which is released into the blood, increasing the concentration

How does insulin and glucagon keep the blood glucose concentration constant?

They work in a negative feedback loop

How does the negative feedback loop for blood glucose concentration work?

When blood glucose levels increase/decrease, a hormone is secreted to oppose the change and the action of this hormone cannot occur continually because when the blood arrives at a certain glucose concentration, the other hormone is produced, resulting in the opposite effect

What is Type 1 diabetes?

When the pancreas cannot produce enough insulin

What happens when someone has diabetes?

Their blood glucose level can rise to a fatal amount

Why would someone with Type 1 diabetes be thirsty?

Glucose is excreted with their urine and lots of urine is produced

How is Type 1 diabetes treated?

Insulin injections at meal times, which results in glucose being taken up from the bloodstream

Why is it advised for someone with Type 1 diabetes to limit their intake of simple carbohydrates?

They contain lots of glucose

How are doctors attempting to cure Type 1 diabetes?

Pancreas and pancreatic cell transplants and genetically engineering pancreatic cells from mice to make insulin

What is Type 2 diabetes?

When the body no longer responds to insulin

What is a risk factor for Type 2 diabetes?

Obesity

What treatments are there for Type 2 diabetes?

Reducing the number of simple carbohydrates in diet, losing weight and increasing exercise, drugs that make insulin more effective on body cells and help the pancreas make more insulin