Day: June 28, 2022


Temperature is the degree of hotness or coldness of a substance. It is the most important ecological factor affecting almost all the metabolic activities of the Organism. Every physiological function has an optimum temperature at which it show the maximum metabolic rate.

The vertical temperature gradient over Earth’s surface is called lapse rate. This value comes equal to 6.50C per 1000mElevation.Change in temperature is affected by factors like latitude, altitude, Topography, vegetation and slope. Temperature shows a great amount of variation altitudinally and latitudinally.

The bacteria and cyanobacteria are known to survive even in thermal spring (60-900C) or permafrost (–30 to –500C) But most of the organisms are killed By higher temperatures due to denaturation of enzymes while others are killed By very low temperature due to freezing of body fluids except dry seeds, spores And cysts which have no water.

Tolerance power to the extremes of temperature varies from species to species.