19.7

Question 1

Two types of skin?

Answer 1

Hairy skin - on most of body.

Glabrous skin - on palms of hands and soles of feet.

Question 2

In ___ skin, there are ___ types of mechanoreceptors.

Answer 2

Glabrous skin

4 types

Question 3

The 4 types of mechanoreceptors are: ___ ___, ___ ___, ___ ___ and ___ ___.

Answer 3

Meissner corpuscles
Merkel complexes
Ruffini organs
Pacinian corpuscles

Question 4

The two superficial mechanoreceptors of glabrous skin are ___ ___ and ___ ___.

Answer 4

Meissner corpuscles

Merkel complexes

Question 5

The two deep mechanoreceptors of glabrous skin are ___ ___ and ___ ___.

Answer 5

Ruffini organs

Pacinian corpuscles

Question 6

Mechanoreceptors at different levels in the skin sense different ___, and sense ___ distortion of skin.

Answer 6

Energies

Mechanical distortion

Question 7

Mechanical distortion to receptor results in the opening of ___ channels, ___ influx and ___ of part of the axon.

Answer 7

Na+ channels, Na+ influx and depolarisation

Question 8

Match the mechanoreceptor to function:
Meissner, Merkel, Pacinian, Ruffini, to:
Encodes rate of force.
Encodes grip force.
Encodes vibrations.
Encodes hand posture.

Answer 8

Meissner encodes rate of force.
Merkel encodes grip force.
Pacinian encodes vibrations.
Ruffini encodes hand posture.

Question 9

Dermatomes refer to a region of skin supplied by a ___ ___

Answer 9

Spinal nerve.

Question 10

There are ___ pairs of spinal nerves.

Answer 10

31

Question 11

All spinal nerves except ___ are sensory AND motor nerves.

___ is ONLY MOTOR.

Answer 11

C1

C1 is motor ONLY.

Question 12

Territories of skin of spinal nerves and peripheral nerves are ____

Answer 12

Different!

Peripheral nerves generally form plexuses -> not from one segment but from different segments.

Question 13

Skin of the face is innervated by the ___ ___

Answer 13

Trigeminal nerve

Question 14

The 3 branches of the trigeminal nerve are:

Answer 14

Ophthalmic nerve
Maxillary nerve
Mandibular nerve

Question 15

Trigeminal and spinal nerves (to skin of face and body) are ___ ___ fibres.

Answer 15

Large myelinated (due to lots of mechanosensitive fibres).

Question 16

The cell bodies of somatosensory afferents are in the ___ ___ ___ (or ___ ___ for sensory afferents of face).

Answer 16

Dorsal root ganglion.

Trigeminal ganglion.

Question 17

There is only a ___ neuron from the periphery to the brain - this is a ___ neuron.

Answer 17

Single neuron!

Long