S5 S6 Bio Genetics Inheritance Caltec S.5

GENETICS G enetics is the scientific study of heredity and variation among organisms. It is the branch of science that accounts for the occurrence of similarities and differences among organisms of the same species; as well as explaining how traits are transmitted to off springs from their parents. Inheritance refers to the process by which characters/traits are passed from parents to off springs. The importance of genetics It is applied in genetic engineering to produce better breeds and varieties of plants and animals by altering their genetic constitution. It is important in courts of law to determine the paternity of the child. Genetics forms the basis of blood transfusion to determine compatible blood groups. Genetic counselling is important in preventing transmission of genetically determined diseases among married couples. This will help to relieve the families and community of the costs on treatment as well as the suffering of the sick and their families. It can be used in identification of criminals by use of finger prints and DNA profiling. It is used in molecular biology to manufacture artificial enzymes, hormones and vaccines by manipulating responsive genes from organisms. Forms the basis of cloning to increase the number of genetically important plants and animals. DEFNITION OF TERMS USED IN GENETICS Gene; A gene is the basic unit of inheritance that determines the organisms’ characteristics. All the characteristic features of an organism are defined at fertilization by the genes inherited from parents but can be greatly modified by the environment in which the organism lives. Alleles; Are alternative forms of the same gene. Most of the genes occur in two alternative forms called alleles one of which is dominant and the other recessive both of which are represented by alphabetical letters just for study purposes Dominant gene/allele; Is a gene/allele whose trait …