blood glucose levels and obesity 2.8

Question 1

what does chronic elevation of blood glucose levels lead to

Answer 1

the endothelium lining blood vessels taking in more glucose that normal which damages the blood vessels which may result in haemorrhage of blood vessels in the retina, renal failure or peripheral nerve dysfunction

Question 2

homeostasis

Answer 2

the maintenance of steady conditions within the body

Question 3

how is blood glucose concentration maintained

Answer 3

by negative feedback control involving hormones insulin, glucagon and adrenaline

Question 4

insulin

Answer 4

• pancreatic receptors detect high blood glucose levels and the pancreas responds by releasing insulin
• insulin activated the conversion of glucose to glycogen in the liver decreasing blood glucose concentration

Question 5

glucagon

Answer 5

• pancreatic receptors detect low blood glucose levels and the pancreas responds by releasing glucagon
• glucagon activated the conversion of glycogen to glucose in the liver increasing blood glucose concentration

Question 6

adrenaline

Answer 6

• during exercise and fight or flight responses glucose concentrations in the blood are raised by adrenaline which is released from the adrenal glands
• adrenaline stimulates glucagon secretion and inhibits the secretion insulin to increase blood glucose levels

Question 7

diabetes

Answer 7

a condition characterised by failure to lower blood glucose levels

Question 8

type 1

Answer 8

insulin producing cells in pancreas are unable to produce insulin

Question 9

type 2

Answer 9

pancreas can produce insulin but liver cells are less sensitive to it due to a decreased number of insulin receptors

Question 10

diabetes indicators

Answer 10

glucose appearing in urine, thirst, weight loss, tiredness

Question 11

glucose tolerance test

Answer 11

• the blood glucose concentrations of the individual are initially measured after fasting
• the individual then drinks a glucose solution and changes in their blood glucose are measured for at least the next two hours
• the blood glucose concentration of a diabetic usually starts at a higher level than a non diabetic
• during the test a diabetics blood glucose concentration increases to a much higher level than that of a non diabetic and takes longer to return to its starting concentration

Question 12

obesity

Answer 12

a major factor for CVD and type 2 diabetes and is characterised by excess body fat in relation to lean body tissue

Question 13

causes of obesity

Answer 13

high fat diet and decrease in physical activity

Question 14

obesity prevention

Answer 14

• energy intake in the diet should limit the consumption of fats in free sugars as fans have a high calorific value per gramme and free sugars require no metabolic energy to be expanded in their digestion
• exercise increases energy expenditure and preserves lean tissue and can also help to reduce risk factors for CVD by:
• keeping weight under control
• minimising stress
• reducing hypertension
• improving blood lipid

Question 15

BMI

Answer 15

body mass/ height^2

Question 16

BMI category’s

Answer 16

<18.5 underweight
18.5-24.9 normal
25-30 overweight
>30 obese