All living cells in the human body need a continuous supply of

provided mainly by the oxidation of glucose (aerobic respiration).

To guarantee that a regular supply of blood

is available for use by cells regardless of when food is eaten.

This also affects

balance in cells.

All living cells in the human body need a continuous supply of

provided mainly by the oxidation of glucose (aerobic respiration).

To guarantee that a regular supply of blood

is available for use by cells regardless of when food is eaten.

This also affects

balance in cells.

Glucose is stored as

in the liver.

Eating carbohydrate

the concentration of glucose in the blood. This

in blood glucose concentration is detected by receptor cells in the

This causes the pancreas to produce the hormone

.Insulin travels in the blood to the liver, its target organ and stimulates it take up glucose and store it as

. Missing a meal or heavy exercise can result in a

in blood glucose concentration. Such a

is detected by different receptor cells in the

. This causes the pancreas to produce the hormone

. Glucagon travels in the blood to its target organ, the liver and causes liver cells to convert

to

The concentration of glucose in the blood

back to normal levels.

Target tissues have specific

which are a

shape to specific hormones.