MICROANATOMY

Detailed explanation-1: -One group of animal genes containing homeobox sequences is specifically referred to as Hox genes. This cluster of genes is responsible for determining the general body plan, such as the number of body segments of an animal, the number and placement of appendages, and animal head-tail directionality.

Detailed explanation-2: -Homeobox genes are present in the genomes of all animals which have so far been mapped as well as in the genomes of plants and fungi, indicating that the origins are ancient and precede the divergence of these kingdoms. Plants, fungi and unicellular animals do not, however, have clustered homeobox genes.

Detailed explanation-3: -A group of genes known as homeobox (Hox) genes control embryonic development of the body plan in a wide range of animals, from humans and fruit flies to cats to beetles.