Water and Animal Reproduction
Water and Animal ReproductionOrganisms cannot survive without water. First, sperm need a liquid medium to swim in. No sperm, no fertilization.
Second, during development there is much metabolic activity that uses all of the organic molecules that you learned about in another part of this module. Of particular interest is the metabolism of proteins. When an amino acid is removed from a protein, it can be recycled to another protein or it can be catabolized. In order for an amino acid to be metabolized, it must be deaminated. Deamination means that the amine group of the amino acid is removed by an enzyme resulting in ammonia or another metabolic product. Deamination usually occurs in the liver of animals.
Third, nitrogen is an integral part of our nucleic acids. Our food materials include DNA and RNA. This nitrogen must also be eliminated.
There are several different end products of protein metabolism. They include ammonia, urea, uric acid, and guanine. Each of these excretory products progressively requires less and less water. However, the formation of each of these excretory products requires progressively more energy to make. Which question would you like to start with?
Animals living in tidal mud flats will also excrete simple amino acids.
Cheetahs eat a high protein diet, but they can go up to 10 days without water. If you would like to know more, please visit this site to see what cheetahs do when water is limited.
Properties | Movement | Life | Locomotion | Metabolism | Excretion | Reproduction | Adaptation | Ecology | Map
