CRANIAL NERVES OF SCOLIODON (SHARK)

SHARK FISH (SCOLIODON) CRANIAL NERVES ORIGIN AND PHYSIOLOGICAL FUNCTION

Ten pairs of cranial nerves arise from the brain at different loca­tions to supply the anterior region of the body. In addition to them a pair of terminal or pre olfactory nerves (zero nerves) arises from the ventral surface of the cerebrum.

The ten pairs of cranial nerves are furnished below for detail study.

cranial-nerves-scoliodon

 

1. BRANCHIALIS X
3. LATERALIS X
4. BUCCALIS VII
5. CEREBELLUM
6. OPTIC III
7. OPHTHALMICUS SUPERFICIALIS V& VII
8.OLFACTORY LOBE
9.BUCCALIS VII
10. PALATINUS VII
11.MAXILLARIS INFERIOR V
12.MANDIBULARS V
13. MANDIBULARS EXTERNUS VIII
14. HYOMANDIBULARIS VII
15. PHARYNGEAL
16. OPHTHALMICUS PROFUNDUS V
17. POST TREMATIC PRETREMATIC IX IX 
18. MANDIBULARS INTERNUS VII 

 

 

 

Name of the nerve

Origin

 

Branches

 

Distribution

 

Physiological Nature

I. OLFACTORY Olfactory lobe.       Olfactory epithelium of the nasal cavity.   Sensory
               
2. OPTIC Optic lobe.       Retina of eye.   Sensory
               
3. OCULOMOTOR Ventrolateral side ofthe midbrain.       Anterior rectus, superior rectus, inferior rectus and inferior oblique muscles of the eye. Superior oblique muscle of the eye   Motor Motor
               
4 TROCHLEAR Dorsolateral aspect of the midbrain between the optic lobes and cerebrum.       Olfactory capsule and dorsal   Mixed
               
5 TRIGEMINAL Dorsally from the side of medulla oblongata below the corpora restiformes.   (i) Opthalmic profundus (ii) Ophthalmicus superfi-cialis V (iii) Maxillaris V (a) Superior (b) Inferior (iv) Mandibularis   skin of the snout. Skin of the snout. Skin of upper jaw Posterior part of upper lip. Muscles of the lower jaw.   Mixed Motor Mixed
               
6. ABDUCENS Midventrally from the floor of medulla oblongata       Posterior rectus muscle of the eye.   Mixed
7. FACIAL From the side of medulla below the corpora restiformes in the form of a bundle.   (i) Opthalmicus super-ficialisVII (ii) Ramus buccalis (iii) Flyomandibularis (a) Mandibularis exte-rnus (b) Mandibularis inter-nus (c) Hyoidean (iv) Ramus palatinus   Sense organs; the lateral line system of snout. Infra-orbital lateral line canal and associated ampullae. Mandibular canal of lateral-line system. Mucous membrane of the floor of buccal cavity. Muscles of the roof of buccal cavity and pharynx. Roof of the pharyngeal and buccal cavity.   Mixed Mixed Mixed Mixed Mixed Sensory
               
8. AUDITORY From the side of medulla close to the V and Vll cranial nerves.   (i) Vestibular (ii) Saccular   Membranous labyrinth of the internal ear   Sensory
               
9. GLOSSOPHARYN GEAL From the ventro-lateral side of medulla. .   (i) Pre-trematic (ii) Post-trematic   Mucous membrane of the first gill-cleft and the pharynx. The muscles of the pharynx Gills.   Sensory Mixed Mixed
               
10. VAGUS Side of Medulla.   (a) Branchialis (b) Visceralis (c) Lateralis   Viscera. Lateral-line system of the trunk.   Mixed Mixed Mixed

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