Unit 2: Physiology & Health - Key Area 8: Blood Glucose Levels and Obesity

Question 1

What are normal blood glucose levels?

Answer 1

5 millimoles per litre

Question 2

If a person is suffering from diabetes what happens to their blood glucose levels?

Answer 2

Their level of blood glucose could become elevated to an abnormal level.

Question 3

What happens if a persons has chronic elevated blood glucose levels?

Answer 3

The endothelial lining blood vessels absorb far too more glucose than normal. This causes damage to the blood vessels (atherosclerosis) and can lead to peripheral vascular disease, CVD or stroke.

Question 4

How can a person get micro vascular disease and what can this cause?

Answer 4

When the endothelial cells lining a small vessel like an arteriole take in more glucose than normal, the layer of cells lining the wall becomes thicker but weaker. This causes the walls to lose their strength and burst and bleed into the surrounding tissues. Tissues could be affected by being flooded with leaked blood, or not receiving enough oxygen. This is called micro vascular disease and can affect the blood vessels in the retina, and can cause retinal failure or peripheral nerve dysfunction.

Question 5

Why do cells need a supply of glucose?

Answer 5

For respiration for energy.

Question 6

What are the organs and hormones involved in glucose balance?

Answer 6

Pancreas and liver. Insulin and glucagon.

Question 7

When is insulin released into the body?

Answer 7

When glucose levels in the blood increase.

Question 8

What does insulin turn glucose into?

Answer 8

Glycogen

Question 9

When is glucagon released in the body?

Answer 9

When glucose levels in the blood decrease.

Question 10

Where is glycogen found in the body?

Answer 10

In the liver.

Question 11

Where is glucagon made in the body?

Answer 11

The pancreas.

Question 12

Where does glucagon work in the body?

Answer 12

In the liver.

Question 13

Where is glucose found in the body?

Answer 13

In the bloodstream.

Question 14

What does glucagon turn glycogen into?

Answer 14

Glucose.

Question 15

Where are both glucagon and insulin released from?

Answer 15

The pancreas.

Question 16

Where do the hormones glucagon and insulin released from the pancreas travel to?

Answer 16

The liver where they can have an affect and regulate glucose levels in the blood.

Question 17

What happens with regard to blood glucose after someone has eaten?

Answer 17

The person has a normal blood glucose level. They then eat something which causes an increase in blood glucose detected by the receptor cells in the pancreas. The pancreas then responds by releasing more insulin and less glucagon into the blood. The liver then converts glucose in the blood into glycogen fo storage. Blood glucose concentration returns back to a normal level.

Question 18

What happens with regard to blood glucose after someone has excercised?

Answer 18

The person has a normal blood glucose level. They then exercise which causes a decrease in blood glucose detected by receptor cells in the pancreas. The pancreas then responds by releasing more glucagon and less insulin into the blood. The liver now converts glycogen into glucose for release into the blood. The blood glucose concentration returns to a normal level.

Question 19

During a fight or flight reaction when the body needs additional supplies of glucose to provide energy quickly what do the adrenal glands secrete?

Answer 19

An increased volume of adrenaline into the bloodstream.

Question 20

Where is adrenaline secreted from?

Answer 20

The adrenal glands.

Question 21

How does adrenaline provide more glucose to the body?

Answer 21

Adrenaline overrides normal glucose control and inhibits the secretion of insulin and stimulates the secretion of glucagon. This promotes the breakdown of glycogen to glucose and increases blood sugar levels.

Question 22

What can people with diabetes not control?

Answer 22

Their blood glucose levels.

Question 23

At what stage of life does type 1 diabetes normally occur?

Answer 23

Childhood or early teens.

Question 24

At what stage of life does type 2 diabetes normally occur?

Answer 24

Adulthood

Question 25

What is the ability of people with type 1 diabetes to produce insulin?

Answer 25

They are unable to produce insulin.

Question 26

What is the ability of people with type 2 diabetes to produce insulin?

Answer 26

Able to produce insulin.

Question 27

What is the sensitivity of cells to insulin for people with type 1 diabetes?

Answer 27

Cells have the normal number of insulin receptors on their surface. They respond to the presence of insulin.

Question 28

What is the sensitivity of cells to insulin for people with type 2 diabetes?

Answer 28

Cells have decreased number of insulin receptors on their surface making them less sensitive to insulin. This means they cannot convert glucose to glycogen.

Question 29

What is the treatment of type 1 diabetes?

Answer 29

Regular injections of insulin and a careful diet.

Question 30

What is the treatment of type 2 diabetes?

Answer 30

Excercise, diet control, weight loss and in some cases insulin injections.

Question 31

In both type 1 and 2 diabetes what will happen to a sufferer after eating a meal?

Answer 31

Individuals blood glucose levels will increase rapidly after a meal and the kidneys are unable to cope resulting in glucose being lost in the urine.

Question 32

What is the test for diabetes?

Answer 32

The glucose tolerance test which shows how well the blood can deal with ingested glucose levels, by testing urine for glucose, and is used to diagnose diabetes.

Question 33

How does the glucose tolerance test work?

Answer 33

A person fasts and have their fasting blood glucose levels measured. Then they are given 250-300ml of glucose solution and their blood glucose levels are measured again over the next 2 hours. The blood glucose concentration of a diabetic usually starts at a higher level than that of a non-diabetic. During the test the diabetics blood glucose concentration rises to a much higher level than that of a non-diabetic and takes a longer time to return to its starting concentration.

Question 34

What obesity a major risk factor for?

Answer 34

Type 2 diabetes and cardiovascular disease.

Question 35

What are factors that contribute to obesity?

Answer 35

Genetic, psychological, environmental and metabolic factors but the most common are thought to be excessive consumption of food rich in fats and free sugars combined with a lack of exercise.

Question 36

What is obesity categorised as?

Answer 36

Obesity is categorised as excess body fat in comparison to lean tissue such as muscle.

Question 37

How is BMI calculated?

Answer 37

BMI = weight (in kg) / height squared (in m)

Question 38

What BMI is indicates that a person is obese?

Answer 38

A BMI of over 30

Question 39

Why are there limitations to BMI?

Answer 39

Individuals like body builders have an unusual high percentage of muscle which would be wrongly classified as obese.

Question 40

What does exercise increase and prevent?

Answer 40

Exercise increases energy expenditure and prevents lean tissue.

Question 41

How can exercise help to reduce factors for CVD?

Answer 41

Exercise can help to reduce risk factors for CVD by:

• Keeping obesity under control
• Minimising stress
• Reducing blood pressure
• Improving HDL:LDL lipid profiles