Heredity

This chapter explains how traits and characteristics are passed reliably from parents to offspring. We study how variation accumulates during reproduction, the meaning of heredity and inherited traits, and Gregor Mendel's classic pea-plant experiments that revealed the rules of inheritance — dominant and recessive traits, the monohybrid cross (3:1) and the dihybrid cross (9:3:3:1). We then see how genes control characteristics through proteins, why each organism carries two copies of every gene on paired chromosomes, and how the sex of a human child is determined by the sex chromosomes (XX and XY). This is a high-yield, concept-and-numerical chapter for the Class 10 board exam and a foundation for NEET genetics.