6/16/25 Spinal Nerves & Skin

Question 1

What makes up the CNS?

Answer 1

Brain, brainstem, spinal cord

Question 2

What makes up the PNS?

Answer 2

All nervous system structures outside the CNS (cranial and spinal nerves)

Question 3

What does it mean that the CNS and PNS are symmetrical?

Answer 3

Nerves are the same on the left and right sides of the body

Question 4

What does it mean that the CNS and PNS are segmentally arranged?

Answer 4

The nerves are aligned in lateral segments throughout the body

Question 5

How many segments makes up the trunk and limbs?

Answer 5

31 segments of tissues

Question 6

How many segments does the spinal cord have?

Answer 6

31 segments

Question 7

True or False: each spinal cord segment has paired spinal nerves that innervate each trunk/limb segment.

Answer 7

True

Question 8

What is the cell of the nervous system called?

Answer 8

Neuron

Question 9

What kind of neuron is a multipolar neuron?

Answer 9

Motor

Question 10

Where do multipolar neurons carry information?

Answer 10

From the CNS to the target (axon terminals).

Efferent information

Question 11

What kind of neuron is a pseudounipolar neuron?

Answer 11

Sensory

Question 12

Where do pseudounipolar neurons carry information?

Answer 12

From the axon terminals at the target back to the CNS

Afferent information

Question 13

What are axons of multiple neurons traveling together to and from the target?

Answer 13

Nerves

Question 14

True or False: Most nerves contain both motor and sensory axons/fibers

Answer 14

True

Question 15

What are the 3 axons/fiber types of the spinal nerves?

Answer 15

Somatomotor
Sympathetic
Somatosensory

Question 16

Somatomotor innervation

Answer 16

From CNS to skeletal muscle

Question 17

Somatomotor neuron type

Answer 17

multipolar

Question 18

Sympathetic (visceral) innervation

Answer 18

From CNS to smooth muscle and sweat glands

Question 19

Sympathetic (visceral) neuron type

Answer 19

Multipolar

Question 20

Somatosensory innervation

Answer 20

From skin to CNS

Pain, touch, temperature

Question 21

Somatosensory neuron type

Answer 21

Pseudounipolar

Question 22

What are the 2 fiber/axon types of cutaneous nerves?

Answer 22

Somatosensory and sympathetic (visceral)

Question 23

What is a dermatone?

Answer 23

A strip of skin supplied by one spinal nerve pair. Note that adjacent segments have overlapping innervation

Question 24

T4 dermatome

Answer 24

Nipple

Question 25

T10 dermatome

Answer 25

Umbilicus

Question 26

T12 dermatome

Answer 26

Pubic

Question 27

In what neuron cell body does the varicella virus remain dormant?

Answer 27

Somatosensory cell body

Question 28

2 layers of the skin

Answer 28

Epidermis and Dermis

Question 29

What makes up the epidermis?

Answer 29

Hair follicles, sebaceous glands, melanocytes

Question 30

What makes up the dermis?

Answer 30

Arrector pili muscles (smooth muscle), sweat glands, blood vessels, cutaneous nerves

Question 31

What is another name for the hypodermis?

Answer 31

Superficial fascia

Question 32

What makes up the hypodermis?

Answer 32

SubQ loose CT, collagen, adipose tissue

Question 33

Where can you find visceral adipose tissue?

Answer 33

surrounding organs

Question 34

Where can you find SubQ adipose tissue?

Answer 34

Deep to the skin

Question 35

What is the layer directly surrounding the muscle?

Answer 35

Investing/deep fascia

Question 36

What part of the skin is thick and hairless?

Answer 36

Palms of hands and feet

Question 37

Where can you find thin, hairy skin?

Answer 37

Everywhere on the body besides palms of hands and feet

Question 38

What part of the skin is hair derived from?

Answer 38

Epidermis

Question 39

True or False: Each hair follicle is associated with its own sebaceous gland

Answer 39

True

Question 40

What are nails made of?

Answer 40

Specialized epidermis

Question 41

Largest organ in the body

Answer 41

Skin

Question 42

Functions of the skin

Answer 42

Sensation Body temp regulation Barrier protection Vitamin D synthesis

Question 43

True or False: Collagen fibers in the dermis are arranged in the same direction

Answer 43

False. They are arranged in different directions (randomly) in different parts of the body. This should be considered when making incisions to minimize scarring (want to cut parallel to the cleavage/Langer's lines)

Question 44

What do stretch marks do to the collagen of the dermis?

Answer 44

They result from tears in the collagen fibers in the dermis

Question 45

What are keloids?

Answer 45

Overgrowth of collagen during scar formation

Question 46

Fxn of superficial fascia

Answer 46

bridges the skin to deeper structures