The development of a multicellular organism's body system is highly coordinated.
Complete the following passage describing the control of development and tissue remodeling using the most appropriate terms.
The development of a body plan is regulated by genetic factors as well as ............................................\text{............................................}............................................ influences. Internal and external ............................................\text{............................................}............................................ can affect the expression of regulatory genes that control cell proliferation and cell death. The process of programmed cell death, known as ............................................\text{............................................}............................................, is essential for morphogenesis, such as the separation of digits. During this process, intracellular ............................................\text{............................................}............................................ digest the cell components, and the resulting debris is safely cleared via ............................................\text{............................................}............................................ to avoid damaging surrounding healthy tissue. [5]
State the name of the family of regulatory genes that contain a highly conserved 180-base-pair sequence and control the development of the body plan along the anterior-posterior axis. [1]