Sensory nerves, neurons, nerve endings

Question 1

List the mechanoreceptors and categorize them into rapidly or slowly adapting

Answer 1

Rapidly adapting:

1. Pacinian corpuscle (vibration)
2. Meissner’s corpusle (heavy pressure)
3. Hair follicle receptors

Slowly adapting

1. Merkle’s disks (light touch)
2. Ruffini’s ending (skin stretch)
3. Free nerve endings (temperature, mechanical stimuli: touch, pressure, stretch)

Question 2

Thermoreceptors

Answer 2

Are free nerve endings that respond to either increase in temperature or decreases in temperature

Question 3

Proprioceptors and examples

Answer 3

responsible for detecting the position of the body in space. These receptors are continuously active and do not adapt. Ex, muscle spindles, Golgi tendon organs and free nerve endings

Question 4

Nociceptors

Answer 4

are free nerve endings and respond to mechanical, thermal, or chemical stimuli or combinations of all three (polymodal)

Question 5

Define somatosensory receptors

Answer 5

Receptors that are specialized peripheral nerve endings or cells that detect a specific sensory stimuli

Question 6

What are the classes of somatosensory receptors

Answer 6

1. Photoreceptors (vision)
2. Chemoreceptors (taste, smell, pain, blood o2, blood pH)
3. Thermoreceptors (temperature changes
4. Mechanoreceptors (Baroreceptors, osmoreceptors, hair cells)

Question 7

How do osmoreceptors detect osmolarity of extracellular fluid?

Answer 7

Swelling (stretch) of receptor cells

Question 8

How do baroreceptors detect blood pressure ?

Answer 8

Stretching of specific blood vessel wall (carotid sinus & aortic arch)

Question 9

What types of sensory information do hair cells in the ear detect?

Answer 9

1. sound waves via sound vibrations in the air
2. balance and equilibrium through body movements

Question 10

What is a cholinergic neuron?

Answer 10

Is a nerve cell which mainly uses the neurotransmitter ACh to send its messages.

Question 12

Afferent neurons:

Answer 12

sensory neurons that carry nerve impulses from receptors to the CNS

Question 13

Dorsal root ganglion

Answer 13

An enlargement outside of the spinal cord that consists of a collection of cell bodies of the sensory neurons that bring information from the peripheral to the spinal cord. These cell bodies have a long peripheral axon and a short central axon.