Final answer:
The class of receptors that respond to temperature, pain, itch, and hair follicle movement are somatosensory receptors, including free nerve endings and hair follicle receptors.
Step-by-step explanation:
The class of receptors that respond to temperature, pain, itch, and hair follicle movement are somatosensory receptors, specifically free nerve endings and hair follicle receptors. Free nerve endings are the most common nerve endings in skin, sensitive to painful stimuli, temperature changes, and light touch, whereas hair follicle receptors detect hair movement and skin deflection. Thermoreceptors, nociceptors (pain receptors), and mechanoreceptors responsible for the sensation of hair movement are integrated in these functions.
Sensory receptors in the skin, such as Merkel cells, Meissner's corpuscles, and Pacinian corpuscles, each respond to different types of touch or vibration. These, combined with free nerve endings and hair follicle receptors, create a detailed and responsive network that allows us to interact with our environment and detect a variety of sensations.