1.
Which nerve arises from the olfactory epithelium and functions solely by carrying afferent impulses for the sense of smell?
Correct Answer
D. I olfactory
Explanation
The olfactory nerve, also known as cranial nerve I, arises from the olfactory epithelium and is responsible for carrying afferent impulses for the sense of smell. It is the only nerve that functions solely for the sense of smell, making it the correct answer in this case. The optic nerve (cranial nerve II) is responsible for carrying visual information, the glossopharyngeal nerve (cranial nerve IX) is involved in taste and swallowing, and the trochlear nerve (cranial nerve IV) controls eye movement.
2.
Which nerve functions solely by carrying afferent impulses for vision and arises from the retina?
Correct Answer
D. II optic
Explanation
The correct answer is II optic. The optic nerve is responsible for carrying afferent impulses for vision and it arises from the retina. It is the second cranial nerve and plays a crucial role in transmitting visual information from the eye to the brain.
3.
Cranial Nerve III Oculomotor functions in the following:
Correct Answer
A. Functions in raising the eyelid, directing the eyeball, constricting the iris, and controlling lens shape
Explanation
Cranial Nerve III, also known as the Oculomotor nerve, is responsible for various functions related to the eye. It helps in raising the eyelid, allowing us to open our eyes. It also directs the movement of the eyeball, allowing us to look in different directions. Additionally, it controls the constriction of the iris, which regulates the amount of light entering the eye. Lastly, it plays a role in controlling the shape of the lens, which helps in focusing on objects at different distances.
4.
Which nerve is primarily a motor nerve that directs the eyeball:
Correct Answer
A. Trochlear IV
Explanation
The trochlear nerve (IV) is primarily a motor nerve that directs the eyeball. It innervates the superior oblique muscle, which is responsible for downward and outward movement of the eyeball. The other options, trigeminal nerve (V) and vestibulocochlear nerve (VIII), are not primarily involved in directing the eyeball. Therefore, the correct answer is Trochlear IV.
5.
Which nerve conveys sensory impulses from various areas of the face (V1) and (V2) and supplies motor fibers (V3) for mastication?
Correct Answer
D. V Trigeminal
Explanation
The correct answer is V Trigeminal. The trigeminal nerve is responsible for conveying sensory impulses from various areas of the face, including the first (V1) and second (V2) divisions. It also supplies motor fibers (V3) for mastication, which is the movement of the jaw during chewing. The other options, X Vagus, III Oculomotor, and VII Facial, are not involved in the functions described in the question.
6.
This nerve functions solely sensory-providing equilibrium and hearing:
Correct Answer
D. VIII Vestibulocochlear
Explanation
The correct answer is VIII Vestibulocochlear. This nerve is responsible for providing sensory input related to equilibrium and hearing. It carries signals from the inner ear to the brain, allowing us to maintain balance and perceive sound. The other options listed, III oculomotor, XII Hypoglossal, and X Vagus, are not involved in sensory functions related to equilibrium and hearing.
7.
This Nerve is a mixed nerve with motor and sensory functions. The Motor function is to innervate part of the tongue and pharynx and provide motor fibers to the parotid salivary gland. Sensory function is to conduct taste and general sensory impulses from the tongue and pharynx.
Correct Answer
C. IX GlossopHaryngeal
Explanation
The correct answer is IX Glossopharyngeal. This is because the given description matches the functions of the glossopharyngeal nerve. It is a mixed nerve that has both motor and sensory functions. The motor function includes innervating part of the tongue and pharynx, as well as providing motor fibers to the parotid salivary gland. The sensory function involves conducting taste and general sensory impulses from the tongue and pharynx.
8.
This is the only cranial nerve that extends beyond the head and neck. This is a mixed nerve that's sensory function is to taste.
Correct Answer
A. X Vagus
Explanation
The correct answer is X Vagus. The vagus nerve is the only cranial nerve that extends beyond the head and neck. It is a mixed nerve, meaning it contains both sensory and motor fibers. While it has many functions, one of its sensory functions is to transmit taste information from the back third of the tongue and the epiglottis.
9.
All of the cranial nerves serve only the head and neck structures, except which one?
Correct Answer
A. X Vagus
Explanation
The cranial nerves are a set of twelve nerves that originate from the brain and primarily innervate the head and neck structures. The vagus nerve, also known as cranial nerve X, is the only cranial nerve that extends beyond the head and neck region. It travels to various organs in the chest and abdomen, including the heart, lungs, and digestive system. Therefore, the correct answer is X Vagus.
10.
Which Nerve has a name meaning "eye mover" because it supplies the six extrinsic muscles that move the eyeball into orbit?
Correct Answer
D. III oculomotor
Explanation
The correct answer is III oculomotor. The oculomotor nerve is responsible for supplying the six extrinsic muscles that move the eyeball into orbit. The name "oculomotor" refers to its function of controlling eye movement.
11.
This Nerve's name means "pulley," and it innervates an extrinsic eye muscle that loops through a pulley-shaped ligament in orbit.
Correct Answer
C. IV Trochlear
Explanation
The correct answer is IV Trochlear. The trochlear nerve is named after the Latin word "trochlea," which means "pulley." This nerve innervates the superior oblique muscle of the eye, which loops through a pulley-shaped ligament in the orbit. The trochlear nerve is responsible for controlling the movement of the eye in a downward and outward direction.
12.
Which nerve controls the muscle that abducts the eyeball?
Correct Answer
A. VI Abducens
Explanation
The nerve that abducts the eyeball is the VI Abducens nerve. This nerve is responsible for the lateral movement of the eyeball, allowing it to move away from the midline of the body. The VII Facial nerve is responsible for controlling the muscles of facial expression, not eye movement. The V Trigeminal nerve is responsible for sensory information from the face and motor functions such as chewing, but not eye movement. Therefore, the correct answer is VI Abducens.
13.
The nerve that innervates the muscles of facial expression:
Correct Answer
A. VII Facial
Explanation
The correct answer is VII Facial because the facial nerve is responsible for innervating the muscles of facial expression. It controls movements such as smiling, frowning, and raising the eyebrows. The facial nerve also plays a role in sensory functions such as taste perception on the anterior two-thirds of the tongue. Therefore, it is the nerve that directly controls the muscles of facial expression.
14.
Its name meaning "tongue and pharynx," reveals the structures that it helps to innervate.
Correct Answer
B. IX GlossopHaryngeal
Explanation
The correct answer is IX Glossopharyngeal because the name "Glossopharyngeal" refers to the structures it helps to innervate, which are the tongue and pharynx.
15.
Considered an accessory part of the vagus nerve, this nerve was formerly called the spinal accessory nerve.
Correct Answer
C. XI Accessory
Explanation
The correct answer is XI Accessory because the question states that this nerve was formerly called the spinal accessory nerve. This indicates that the nerve being referred to is the XI Accessory nerve, as it was previously known by that name.