Genetics is the study of heredity, or how traits are passed down from parents to offspring. It is a branch of biology that explores the genetic makeup of living organisms, including the structure and function of genes, the mechanisms of inheritance, and the genetic variation that occurs within and between populations.
Genes are the basic units of inheritance, and they are made up of DNA (deoxyribonucleic acid), which contains the instructions for building and maintaining an organism. DNA is organized into structures called chromosomes, which are found in the nucleus of a cell. Humans have 23 pairs of chromosomes, for a total of 46.
In sexual reproduction, the genetic material from two parents is combined to create a unique offspring. The process of meiosis, which occurs in the reproductive cells, ensures that the offspring receives a random assortment of genetic information from each parent.
Genetic variation is the result of mutations, or changes in the DNA sequence. These mutations can be caused by environmental factors, such as radiation or chemicals, or they can occur spontaneously during DNA replication.
Advances in genetics have led to a better understanding of many aspects of biology and medicine, including the diagnosis and treatment of genetic disorders, the development of genetically modified organisms, and the study of evolution and population genetics.