The characters of chromosomes in a particular species are transmitted from one generation to another by the structural and functional unit, called as genes. This chapter covers the Mendel’s laws and mode of inheritance. Gregor Mendel with his vast experience by cultivating pea plants of many generations of plants grown from hybrid seeds postulated his observations as follows as law of segregation, law of independent assortment, and law of dominance. Transmission of characters from one generation to another is inheritance. Hereditary and environment play a role in determining the character. Genetically the individual may have a gene for being tall, but lack of adequate nutrition may inhibit the growth.