In the motor division of the PNS, the effector organs consist of the three types of muscle tissue and glands. Which of these effector organs would be under voluntary control and thereby fall into the somatic nervous system?

The skeletal muscles are the effector organs which are under voluntary control and thereby fall into the somatic nervous system.

Explanation:

The somatic nervous system, especially the central and the peripheral motor division, is responsible for the voluntary movements. They send signals through the efferent nerves which arise from the spinal cord with information passing to and from the sense organs and the muscles which act as the effectors, through the efferent pathway.

This pathway controls voluntary movements of the limbs and the body in general by sending information from the spinal cord and controlling the motor functions required for voluntary movements.

Through efferent innervations, the somatic nervous system activates and controls the skeletal muscles to perform voluntary actions.