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The maintenance of a constant internal environment

Homeostasis involves maintaining the chemical make-up, volume and other features of blood and
tissue fluid within restricted limits.
The internal environment is made up of tissue fluids that bathe each cell, supplying nutrients and
removing wastes.
Homeostasis ensures all the cells of the…

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The control of any self-regulating system involves a series of stages that feature:

The set point which is the desired level at which the system operates which is
monitored by the...
Receptor which detects any deviation from the set point and informs the...
Controller which coordinates information from various receptors…

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Temperature Homeostasis: Thermoregulation

One of the most important examples of homeostasis is the regulation of body temperature.
Body temperature needs to be regulated to keep enzymes working close to their optimum
temperature and to prevent them from denaturing.
There are basically two ways of doing this: mammals and birds can…

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Temperature Homeostasis in Endotherms

Endotherms gain most of their heat from internal metabolic activities.
Their body temperature remains relatively constant despite fluctuations in the external temperature.

The core body temperature is between 35-44Oc.
This range is a compromise between having a higher temperature at which enzymes work more rapidly

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Regulation of body temperature in endotherms is an example of homeostasis.
The stimulus is detected by thermoreceptors which pass the information to a coordinator ­ the
hypothalamus, in the brain which then causes an effector ­ the skin, to produce the appropriate

Within the hypothalamus there is a thermoregulatory…

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Glucose is the transport carbohydrate in animals, and its concentration in the blood affects every cell in
the body.
The brain in particular can only respire glucose (not lipids) but it doesn't store glycogen.
Very low concentrations of glucose (hypoglycaemia) will cause brain cells to die and very high

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The Role of the Pancreas in Regulating Blood Glucose

The pancreas is a large, pale-coloured gland that is situated in the upper abdomen, behind the stomach.

It produces enzymes: protease, amylase and lipase for digestion
It produces hormones: insulin and glucagon for regulating blood glucose

The pancreas is made up…

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Role of Adrenaline in regulating the blood glucose level

Adrenaline is a hormone that is secreted from your adrenal glands.
It's secreted when there's a low concentration of glucose in your blood.

Adrenaline raises the blood glucose by:

· Activating an enzyme that causes the breakdown of glycogen to glucose…

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Diabetes is a chronic disease in which a person is unable to metabolise carbohydrates, especially
glucose, properly.

Types of Diabetes

Diabetes is a metabolic disorder cause by an inability to control blood glucose levels due to a lack of
the hormone insulin of a loss of responsiveness to insulin.



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