Saturday, September 22, 2012

a house cat or an African lion caged

Which animal must eat a larger proportion of its weight food each day: a house cat or an African lion caged in a zoo?

The house cat must eat a larger proportion food each day, because a house cat has a higher metabolic rate. Metabolic rate is a total amount of energy an animal uses in a unit of time. The house cat usually actives and has higher metabolic rates during daylight hours and sometimes at night or during the hours of dusk and dawn to kill its prey, for example mice. But an African lion caged in a zoo, usually actives during daylight hours, and perhaps at night a lion caged in zoo is only idle, it doesn’t kill its prey because a lion is in the zoo not in the forest. Physiologists have decided that amount of energy it takes to keep up each gram of body weight is contrary related to body size. The higher metabolic rate of a smaller animal’s body tissues like a house cat requires in proportion greater rate of transfer of oxygen to the tissues. One hypothesis has explained about the opposite connection between metabolic rate and body size is that the smaller mammal like a house cat also has higher breathing rate, blood volume, and heart rate. The smaller animal has the greater the energy rate of maintaining an unchanging body temperature. It means the smaller animal is better its surface area to volume ratio, therefore the house cat is greater the loss of heat to, or get from the environment than an African lion caged in the zoo.