A barefooted individual steps on a piece of broken glass and rapidly raises her foot from the glass, while simultaneously balancing her weight to stand on the opposite leg. The reason the same stimulus causes one set of muscles to contract while their antagonists relax is because (select all that apply)
A) spinal interneurons release excitatory neurotransmitters on the motor neurons of effector muscles
B) spinal interneurons release inhibitory neurotransmitters on the motor neurons of antagonist muscles
C) sensory neurons release excitatory neurotransmitters on the motor neurons of effector muscles
D) sensory neurons release inhibitory neurotransmitters on the motor neurons of antagonist muscles

Question

Quizplus · Accepted Answer

Spinal interneurons play a crucial role in reflex actions. They release excitatory neurotransmitters to activate motor neurons of the effector muscles and inhibitory neurotransmitters to relax the antagonist muscles, facilitating a coordinated response.

A Barefooted Individual Steps on a Piece of Broken Glass