Practical Exam 1

Question 1

What are the 12 Cranial Nerves in order?

Answer 1

1. Olfactory - Used for scent
2. Optic - Contains that optic nerve & chiasma
3. Oculomotor - Used for eye movement, posterior to the optic chiasma
4. Trochlear - Enters the superior aspect of the eye
5. Trigeminal - Facial & Jaw nerves, has 3 brances
6. Abducens - Used for eye movement
7. Facial - Large clusters of nerves that run into the face
8. Vestibulocochlear - Used for balance & hearing, posterior to facial nerves
9. Glossopharyngeal - Runs into the tongue & pharynx
10. Vagus - Runs inferior to the thoracic cavity to regulate the heart, lungs, digestive, etc.
11. Accessory - Runs to neck & back muscles
12. Hypoglossal - Runs under the tongue, used for swallowing & speech

Question 2

What are the three meninges (layers of tissue) surrounding the spinal cord?

Answer 2

Dura mater - Outermost double-layer membrane

Arachnoid mater - Web-like middle layer

Pia mater - Innermost layer, touches the brain & spinal cord

Question 3

When a nerve splits as it enters the spinal foramen, what does it split into?

Answer 3

Dorsal Root - bulbous, thicker root; the most posterior of the two

Ventral Root - thinner root; the most anterior of the two branches

Question 4

What are the 5 components of a Reflex Arc?

Answer 4

1. The receptor is the site of stimulus action
2. The sensory neuron transmits an afferent impulse to the Central Nervous System (CNS)
3. The integration center consists of one or more neurons in the CNS
4. Motor Neuron
5. Effector

Question 5

What are the three Auditory Ossicles (Ear Bones)?

Answer 5

Malleus - The “hammer”
Incus - The “anvil”
Stapes - The “stirrup” inferior to the incus

Question 6

Where does the phrenic nerve originate?

Where does it innervate?

Answer 6

Origin: C3 - C5 Nerve Roots of the Cervical Plexus

Innervates the diaphragm

Question 7

Where does the axillary nerve originate?

Where does it innervate?

Answer 7

Origin: C5 & C6 Nerve Roots of the Brachial Plexus

Innervates the deltoid & teres minor as well as some skin of the shoulder region

Question 8

Where does the femoral nerve originate?

Where does it innervate?

Answer 8

Origin: L2 - L4 Nerve Roots of the Lumbar Plexus

Innervates the skin of the anterior and medial thigh, skin of the foot, hip, & knee joints, anterior motor muscles (quadriceps & sartorius), the pectineus, & the iliacus

Question 9

Where does the obturator nerve originate?

Where does it innervate?

Answer 9

Origin: L2 - L4 Nerve Roots of the Lumbar Plexus

Innervates the adductor magnus, longus, & brevis muscles, the gracilis, and the skin of the medial thigh

Question 10

Where does the sciatic nerve originate?

Where does it innervate?

Answer 10

Origin: L4 - S3 Nerve Roots of the Sacral Plexus

Innervates the skin of the lower leg. The sciatic nerve branches proximal to the knee, creating the Tibial and Common Fibular Nerves