Twelve pairs of cranial nerves

nerves correspond to a set of nerve fibers joined by dense connective tissue, organized in bundles and responsible for the transmission of nerve impulses. sensory fibers carry impulses from cells to the central nervous system; motor fibers, from the central nervous system to the muscles.

→ cranial nerves

Cranial nerves depart from the brain, in twelve pairs, connecting it to sense organs and muscles, especially those located in the head region.

Mind Map: Cranial Nerves

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Are they:

I - olfactory nerve

It is a sensory nerve and, as its name suggests, it transmits impulses related to the smell.

II - Optic nerve

Also sensitive. Its fibers are related to the visual impulses.

III- Oculomotor nerve

Motor nerve that is related, as its name implies, to eye movement. It is important to point out that this nerve is related to four of the six external muscles that move this important structure.

IV- Trochlear nerve

This nerve is the smallest of the cranial nerves. It innervates the superior oblique muscle of the eye.

V- Trigeminal nerve

It is a mixed nerve: motor fibers are related to the muscles of mastication; and the sensitive send messages from the eyes, tear glands, eyelids, teeth, gums, lips, palate, facial skin and scalp.

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VI- Abducens nerve

Predominantly motor type nerves that are responsible for information related to eye movements, as well as the adjustment of focus and light. Some sensory fibers act on information regarding the individual's muscular conditions.

VII- Facial nerve

Mixed nerve. Motor fibers provide impulses related to facial expression and tear release and Spittle. Sensory fibers are responsible for aspects related to taste.

VIII- Vestibulocochlear nerve

This sensory nerve is related to body balance and hearing.

IX- Glossopharyngeal nerve

The mixed type. Sensory fibers are responsible for impulses originating from the pharynx, tonsils, tongue and carotids; and the motor, for carrying impulses to the salivary glands and pharyngeal muscles.

X- Vague nerve

Mixed nerve that is related to heartbeat, lung function and digestive system, speech and swallowing.

XI- Accessory nerve

Motor nerve that sends messages to shoulders, neck, pharynx, larynx and soft palate.

XII- Hypoglossal nerve

Motor nerve responsible for the movements of the tongue, pharynx and larynx muscles.

* Mind Map by Ma. Vanessa dos Santos

By Mariana Araguaia
Graduated in Biology

Would you like to reference this text in a school or academic work? Look:

ARAGUAIA, Mariana. "Twelve pairs of cranial nerves"; Brazil School. Available in: https://brasilescola.uol.com.br/biologia/doze-pares-de-nervos.htm. Accessed on June 27, 2021.