Final answer:
Hox genes are the regulatory genes that kick into gear after the embryo is more developed. They play a crucial role in specifying body parts to develop in the correct place.
Step-by-step explanation:
After the embryo is more developed, the regulatory genes that kick into gear are the Hox genes. Hox genes are a group of genes that regulate development during the embryonic stage. They play a crucial role in specifying body parts, such as limbs, to develop in the correct place. For example, in insects, a mutation in a hox gene can lead to abnormal development of body parts.