we know that a cell is the structural and fundamental unit of life. at the very young stage of an organism, the number of cells is less in its body. the organism grow by the increment of the number and size of the cells. matured cells can be divided into new cells and process is called cell division. a eukaryotic cell consists of the major three parts: plasma membrane, cytoplasm and nucleus.
Nucleus is the controlling Centre of a cell as it control all the processing occurs inside the cell. A cell has thread like structures called chromosomes, inside its nucleus which contain genetic material like RNA and DNA. The genetic materials pass the parents; characters from one generation. Due to this reason, puppies resemble their parent dogs, kittens resemble their parent cats and so on. The process of transmission of characters from one generation to another generation is called heredity. The mechanism of heredity and variation is the dissimilarly among the organisms of the same species. Are all the puppies of the same parents similar or different?
Gene and genetic technology are being very useful in human life in different ways. Cross breeding selective breeding etc. are few simple examples of genetic technology being used globally to get rid of different disease and grow more resistant type of plant and animal species. This technology is also being useful for the improvement of human health. It this unit, we are going to study about different types of cell division, different components of chromosome, law of genetics and genetic technology.
Chromosome
living cells are active membrane bond protoplasm's capable of self-reproduction. Their division and growth of multicellular organisms. Eukaryotic cells contain a nucleus. The nucleus of all plants and animals cell serves as the command Centre of the cell or brain of the cell. This is the because the nucleus regulates cells growth development division and ageing. It contains a very fine thin long network of fibres called chromatin fibres. During cell division, the chromatin fibers become shortened and thickened to form chromosomes structure due to condensation. Chromosome are long, thick coiled and thread like microscopic structures found in the nucleus. Chromosomes have the genetic substance that help in the inheritance of characters from parents to offspring .