Biology - Responses to Environmental Effects
Responses to Environmental Effects
The conditions in different environments vary considerably and affect an
organism's ability to maintain a relatively constant internal environment.
Organisms have combinations of structural, physiological (functional) and
behavioural adaptations or features which enable them to survive.
An animal which has no homeostatic mechanisms is subject to changes in the
external environment; e.g. the body temperature of a fish will come to be
the same as the external temperature. This may be higher or lower than the
optimum temperature for enzyme activity. The animal can therefore only live
where external conditions are fairly constant or within the tolerance
limits for the species.
Goldfish: its level of activity is affected by water temperature. View the
These usually act to restore values to normal for a homeostatic organism.
If conditions change to the extent homeostasis cannot be maintained, the
organism will die.
The ability of an organism to cope with changing conditions depends on:
* its own characteristics
* its tolerance limits for different factors
* its structure
* its behaviour
Previous | Next