Lab 4 - Peripheral Nervous System

The ventral horn of the spinal cord contains cells bodies of

**Motor (efferent) neurons** carrying impulses away from the spinal cord to the skeletal muscles

A dorsal root ganglion contains cell bodies of

**Sensory (afferent) neurons** from the skin to the spinal cord

How many pair of cervical nerves are there?

8

Which branch of the cervical plexus innervates the posterior part of the auricle of the ear

Lesser Occipital Nerve

Name the highlighted nerve that provides some of the innervation to joints of the hands.

Median nerve

Motor Innervation of adductor muscles in the leg

Obturator nerve

Sacral Plexus (3 nerves)

Sciatic nerve, Superior gluteal nerve, and tibial nerve

Dorsal rami of spinal nerves innervate

Skin and muscles of the back

Determine the nerves that demonstrate innervation of the teres major muscle

Subscapular nerve

Which nerve provides cutaneous innervation to the skin of the leg and the skin over the dorsum of the foot?

Superficial fibular nerve

Which nerve provides cutaneous innervation to the posterior, distal, and lateral proximal leg

Sural nerve

Which nerve innervates most of the intrinsic muscles of the hand, such as the hypothenar group, lumbricals 3 and 4, and all the interossei muscles?

Ulnar nerve

How many pair of sacral nerves are there?

5

How many pair of coccygeal nerves are there?

1

How many pair of thoracic nerves are there?

12

How many pair of spinal nerves are there?

31

How many pair of lumbar nerves are there?

5

A spinal nerve is formed by the union of

A dorsal and ventral root

What is the name of the highlighted structure, which translates as "neck loop" when deconstructed into its Latin roots?

Ansa cervicalis

Lumbar Plexus (2 nerves)

Femoral nerve & Obturator nerve

Identify the nerve which provides motor innervation to the cremaster muscle in males

Genitofemoral nerve

Which highlighted structure emerges from the cervical plexus and innervates the diaphragm?

Phrenic Nerve

Which nerve provides all motor innervation to the diaphragm?

Phrenic Nerve

Cervical Plexus (2 nerves)

Phrenic nerve & Ansa Cervicalis

Brachial Plexus (3 nerves)

Radial nerve, ulnar nerve, and median nerve

Ventral rami of spinal nerves innervate

lateral and ventral skin AND muscles of the trunk AND the skin of the limbs