No.NameSensory, motor, or bothIOlfactoryPurely sensoryIIOpticSensoryIIIOculomotorMainly motorIVTrochlearMotor

Table of Contents

What are the three major functions of the cranial nerves?

What is the 4th cranial nerve?

The fourth cranial nerve controls the actions of one of the external eye muscles, the superior oblique muscle. This muscle runs from the back of the eye socket to the top of the eye. It passes through a loop of tissue near the nose known as the trochlea. It turns the eye inward and downward.

What are cranial nerves 2 and 3?

The nerves are: the olfactory nerve (I), the optic nerve (II), oculomotor nerve (III), trochlear nerve (IV), trigeminal nerve (V), abducens nerve (VI), facial nerve (VII), vestibulocochlear nerve (VIII), glossopharyngeal nerve (IX), vagus nerve (X), accessory nerve (XI), and the hypoglossal nerve (XII).

What is cranial nerve II?

The optic nerve is the second cranial nerve (CN II) responsible for transmitting visual information. The optic nerve contains only afferent (sensory) fibers, and like all cranial nerves is paired.

Which is the largest cranial nerve?

The vagus nerve (cranial nerve [CN] X) is the longest cranial nerve in the body, containing both motor and sensory functions in both the afferent and efferent regards.

What is the hypoglossal?

The hypoglossal nerve enables tongue movement. It controls the hyoglossus, intrinsic, genioglossus and styloglossus muscles. These muscles help you speak, swallow and move substances around in your mouth.

What is Vestibulocochlear?

The vestibulocochlear nerve (auditory vestibular nerve), known as the eighth cranial nerve, transmits sound and equilibrium (balance) information from the inner ear to the brain.

How many nerves are there in human body?

Believe it or not, there are over 7 trillion nerves in the human body. All these nerves are part of what’s known as your body’s nervous system. You can think of nerves as your body’s electrical wiring — they transmit signals between your brain, spinal cord, and the rest of your body.

How many pairs cranial nerves are there?

In higher vertebrates (reptiles, birds, mammals) there are 12 pairs of cranial nerves: olfactory (CN I), optic (CN II), oculomotor (CN III), trochlear (CN IV), trigeminal (CN V), abducent (or abducens; CN VI), facial (CN VII), vestibulocochlear (CN VIII), glossopharyngeal (CN IX), vagus (CN X), accessory (CN XI), and …

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Is a medulla oblongata?

Medulla oblongataSection of the medulla oblongata at about the middle of the olivary bodyDetailsPart ofBrain stemIdentifiers

What is spiral cord?

A column of nerve tissue that runs from the base of the skull down the center of the back. It is covered by three thin layers of protective tissue called membranes. The spinal cord and membranes are surrounded by the vertebrae (back bones).

What is fifth cranial nerve?

The trigeminal nerve is the fifth cranial nerve (CN V). Its primary function is to provide sensory and motor innervation to the face. … The ophthalmic nerve is responsible for sensory innervation of the face and skull above the palpebral fissure as well as the eye and portions of the nasal cavity.

Why is it called trigeminal nerve?

Its name (“trigeminal” = tri-, or three, and – geminus, or twin: thrice-twinned) derives from each of the two nerves (one on each side of the pons) having three major branches: the ophthalmic nerve (V1), the maxillary nerve (V2), and the mandibular nerve (V3).

What is a Trochlea?

Trochlea (Latin for pulley) is a term in anatomy. It refers to a grooved structure reminiscent of a pulley’s wheel.

What is the ninth cranial nerve?

The glossopharyngeal nerve is the 9th cranial nerve (CN IX). It is one of the four cranial nerves that has sensory, motor, and parasympathetic functions. It originates from the medulla oblongata and terminates in the pharynx.

What is the name of cranial nerve 1?

Cranial nerve 1Olfactory nerve (CN I) – sensoryCranial nerve 2Optic nerve (CN II) – sensoryCranial nerve 3Oculomotor nerve (CN III) – motorCranial nerve 4Trochlear nerve (CN IV) – motorCranial nerve 5Trigeminal nerve (CN V) – mixed

What is the 1st cranial nerve?

The olfactory nerve is typically considered the first cranial nerve, or simply CN I, that contains sensory nerve fibers relating to the sense of smell.

What cranial nerves swallow?

The glossopharyngeal nerve enervates muscles involved in swallowing and taste.

What are the 12 cranial nerve?

Is hypoglossal nerve a mixed nerve?

CN XII, Hypoglossal, innervates the muscles of the throat and enables us to swallow. Five cranial nerves have mixed sensory, motor and parasympathetic function.

Which is the smallest cranial nerve?

– The trochlear nerve is the smallest cranial nerve. It is the fourth cranial nerve.

Which is the smallest nerve in human body?

Trochlear nerve is the smallest cranial nerve. Out of the 12 pairs of cranial nerves, the fourth paired cranial nerve, the trochlear nerve is the smallest of all by virtue of the number of axons.

What is the shortest cranial nerve?

Excerpt. The trochlear nerve is the fourth cranial nerve (CN IV) and one of the ocular motor nerves that controls eye movement. The trochlear nerve, while the smallest of the cranial nerves, has the longest intracranial course as it is the only nerve to have a dorsal exit from the brainstem.

What is the largest nerve in the body?

The sciatic nerve is the largest and longest nerve in the human body, originating at the base of the spine and running along the back of each leg into the foot.

Are there 213 bones in the human body?

There are typically around 270 bones in human infants, which fuse to become 206 to 213 bones in the human adult. The reason for the variability in the number of bones is because some humans may have a varying number of ribs, vertebrae, and digits.

Which is the strongest nerve in human body?

sciatic nerve, largest and thickest nerve of the human body that is the principal continuation of all the roots of the sacral plexus.

Where is the cochlear?

While the cochlea is technically a bone it plays a vital role in the function of hearing rather than simply being another component of the skeletal system. It is located within the inner ear and is often described as hollow and snail- or spiral-shaped.

What is the function of vagus nerve?

The vagus nerve is responsible for the regulation of internal organ functions, such as digestion, heart rate, and respiratory rate, as well as vasomotor activity, and certain reflex actions, such as coughing, sneezing, swallowing, and vomiting (17).

What are the 31 pairs of spinal nerves?

In humans there are 31 pairs: 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal. Each pair connects the spinal cord with a specific region of the body. Near the spinal cord each spinal nerve branches into two roots.

Do all mammals have 12 pairs of cranial nerves?

There are 12 pairs of cranial nerves in mammals including olfactory, visual, oculomotor, trochlear, trigeminal, abducens, facial, vestibulocochlear, glossopharyngeal, vagus, peripheral, and hypoglossal. … So, 12 pairs of cranial nerves in mammals would be the correct answer. Hence, The correct answer is option (C).