What is the basic unit of heredity?

The basic unit of heredity is a gene. Genes are segments of DNA that contain the instructions necessary for the development, functioning, growth, and reproduction of living organisms. They act as the units that convey hereditary information from parents to offspring, determining various traits and characteristics such as eye color, hair type, and susceptibility to certain diseases.

In the context of heredity, genes are crucial because they are passed down through generations and are responsible for the genetic variation observed within species. Each gene occupies a specific position on a chromosome and can have different forms known as alleles, which contribute to the diversity in traits among individuals.

The other terms, while related to heredity and genetics, are not the fundamental units of heredity. Chromosomes are structures within cells that contain many genes. RNA plays various roles in the expression of genes, such as being involved in protein synthesis, but it is not a unit of heredity itself. Alleles are alternative forms of a gene, but they are specific variations rather than the basic units.