Gonads are the reproductive organs in animals that produce gametes, which are the cells necessary for reproduction. In males, the gonads are called testes, which produce sperm cells. In females, the gonads are known as ovaries, which produce egg cells. Gonads also produce hormones that play a crucial role in sexual development and reproduction. These organs are essential for sexual reproduction, allowing for the combination of genetic material from two parents. In addition to their reproductive functions, gonads influence secondary sexual characteristics, such as body hair and breast development, through the hormones they release, including testosterone and estrogen.