Which Statement Applies to Receptors

Question

Which statement applies to receptors
A)They are present for every modality in the environment.
B)When stimulated, they bring about opening of K⁺ channels in the efferent neuron membrane.
C)When mechanical, they are sensitive to varying amounts of heat.
D)They may be either a specialized ending of an afferent neuron or a special cell closely associated with the peripheral ending of an afferent neuron.

Accepted Answer

Receptors can either be specialized endings of an afferent neuron or special cells closely associated with the peripheral ending of an afferent neuron. Option A is incorrect because receptors are specific to certain modalities, such as light or sound, and not present for every modality. Option B is incorrect because receptors do not bring about the opening of K⁺ channels in the efferent neuron membrane, but rather generate a signal that is transmitted by the afferent neuron to the central nervous system. Option C is incorrect because receptors that are sensitive to mechanical stimuli are not typically sensitive to heat, and vice versa.