Week 10:Heredity

What is heredity?  Heredity is the passing on of physical or mental characteristics genetically from one generation to another. Nuclei of living cells contain tiny rod like structures in pairs, they are called as chromosomes. This two sets appear upon examination to be identical or nearly so. Although the chromosomes may vary markedly in size and shape, each chromosome will have a mate of approximately the same size and shape. We have to know that the number of chromosomes varies from one species of animal or plant to another. In human beings there are twenty three pairs. First was discovered that the chemical carrier of hereditary traits is not protein but a chemical, DNA for short which is centered in the nuclei of cells. RNAa near replique of DNA moves out of cell nuclei into the cells’ cytoplasm or outer layers. Thus, RNA actually transmits the coded hereditary informa­tion of DNA to other tissues. Those two concept are defined and explained in week 3 and 4.

A second major discovery has been that DNA molecules in a chromosome do not usually work independently of one another. They tend to work in teams. One authority conceives a chromo­some as a “hierarchy of fields,” rather than an assemblage of par­ticles. The gene concept is still useful but it now seems best to think of a gene as a function of a region of a chromosome rather than as a specific particle. Like we can see the DNA is a huge important element in case of genetics and heredity. Summarizing you now ca know that when we say that a hereditary characteristic, like skin color, is governed by a gene group, we really mean a pair of gene groups. Biology have a lot of theme but this one is some of the most important because with this we can know better about human creation.