Genetics is the study of genes, genetic variation, and heredity in living organisms. A gene is the basic physical and functional unit of heredity. Genes, which are made up of DNA, act as instructions to make molecules called proteins.
The Human Genome Project has estimated that humans have 20,000 - 25,000 genes. Every person has two copies of each gene, one inherited from each parent. Most genes are the same in all people, but less than 1% of genes are slightly different between people. Poplar tree genome suggests more than 45,000 genes.
In botany, a fruit is the seed-bearing structure in flowering plants (for example, cherries, berries, bean pods, corn kernels, tomatoes, grains). "Fruit" normally means the fleshy seed-associated structures of a plant that are sweet or sour, edible in the raw state (apples, grapes, lemons, strawberries, etc).
Edible fruits have propagated with the movements of humans and animals in a symbiotic relationship as a means for seed dispersal and nutrition. Humans and many animals have become dependent on fruits as a source of food.