Question # 02: Explain the functions of any 06 pairs of cranial nerves.
Your cranial nerves are pairs of nerves that connect your brain to different parts of your head,
neck, and trunk. There are 12 of them, each named for their function or structure.
Each nerve also has a corresponding Roman numeral between I and XII. This is based off their
location from front to back. For example, your olfactory nerve is closest to the front of your
head, so it’s designated as I.
I. Olfactory nerve
The olfactory nerve transmits sensory information to your brain regarding smells that you
encounter. When you inhale aromatic molecules, they dissolve in a moist lining at the roof of
your nasal cavity, called the olfactory epithelium. This stimulates receptors that generate nerve
impulses that move to your olfactory bulb. Your olfactory bulb is an oval-shaped structure that
contains specialized groups of nerve cells.
From the olfactory bulb, nerves pass into your olfactory tract, which is located below the frontal
lobe of your brain. Nerve signals are then sent to areas of your brain concerned with memory and
recognition of smells.
II. Optic nerve
The optic nerve is the sensory nerve that involves vision.
When light enters your eye, it comes into contact with special receptors in your retina called rods
and cones. Rods are found in large numbers and are highly sensitive to light. They’re more
specialized for black and white or night vision. Cones are present in smaller numbers. They have
a lower light sensitivity than rods and are more involved with color vision. The information
received by your rods and cones is transmitted from your retina to your optic nerve. Once inside
your skull, both of your optic nerves meet to form something called the optic chiasm. At the
optic chiasm, nerve fibers from half of each retina form two separate optic tracts. Through each
optic tract, the nerve impulses eventually reach your visual cortex, which then processes the
information. Your visual cortex is located in the back part of your brain.
III. Oculomotor nerve
The oculomotor nerve has two different motor functions: muscle function and pupil response.
Muscle function. Your oculomotor nerve provides motor function to four of the six muscles
around your eyes. These muscles help your eyes move and focus on objects. Pupil response. It
also helps to control the size of your pupil as it responds to light. This nerve originates in the

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