Q. The number of cranial nerves in mammals that are purely sensory are
Solution:
• There are 12 pairs are cranial nerves present in the human and rabbit (in all amniotes).
• In frog (and other anamniotes), 10 pairs cranial nerves are present.
• I, II and VIII (olfactory, optic and auditory) i.e., three pairs are sensory cranial nerves. Ill, IV, VI, XI and XII are motor cranial nerves. V, VII, IX and X are mixed cranial nerves.
• Trochlear nerve is the smallest and thinnest cranial nerve. Trigeminal (dentist nerve) is the largest cranial nerve.
Number
Name
I
Olfactory
II
Optic
III
Oculomotor
IV
Pathetic/Trochlear
V
Trigeminal
VI
Abducens
VII
Facial
VIII
Auditory (Acoustic)
IX
Glossopharyngeal
X
Vagus
XI
Accessory Nerve/Spinal accessory
XII
Hypoglassol
| Number | Name |
|---|---|
| I | Olfactory |
| II | Optic |
| III | Oculomotor |
| IV | Pathetic/Trochlear |
| V | Trigeminal |
| VI | Abducens |
| VII | Facial |
| VIII | Auditory (Acoustic) |
| IX | Glossopharyngeal |
| X | Vagus |
| XI | Accessory Nerve/Spinal accessory |
| XII | Hypoglassol |