Unit 5 - Nervous System

Abducens nerve function

abducts the eyeball by innervating the lateral rectus muscle

Radial nerve

innervates the triceps, supinator, and brachioradialis

1. Olfactory

2. Optic

3. Oculomotor

4. Trochlear

5. Trigeminal

6. Abducens

7. Facial

8. Vestibulocochlear

9. Glossopharyngeal

10. Vagus

11. Accessory

12. Hypoglossal

Accessory Nerve

innervates the trapezius muscle, formed from ventral rootlets of spinal cord

External acoustic meatus

ear canal

Anterior cavity

Anterior and posterior chambers

Arachnoid mater function

contains major blood vessels, has web-like threads

Arbor vitae

Auricale/pinna

Autonomic motor

involuntary innervation of smooth muscle, cardiac muscles and glands

Axillary nerve

Axillary nerve function

innervated the deltoid and teres minor; stems from the posterior cord

5 Rami, 3 Trunks, 6 Divisions, 3 Cords, 5 Nerves

Brachial plexus hierarchy

Brain stem

made up of the midbrain, pons, and medulla oblongata

Brain ventricles

expansions of the brain’s central cavity filled with CSF; continuous with eachother and the central canal

Buccal branch

Central canal

Cerebral hemispheres

symmetrical halves on cerebrum

Cerebellar nuclei

deeply situated in the gray matter of the cerebellum

Cerebellum

Cerebrospinal fluid

fills the hollow cavities of the brain and spinal cord to provide a liquid cushion

Cerebral aqueduct

Cervical plexus

formed by ventral rami of C1-C4; under the sternocleidomastoid muscle

Choroid function

posterior portion that prevents light scatter due to brown colour; has vasculature, connective tissue and melanocytes

Choroid

Ciliary body

anterior portion that controls the shape of the lens; acts as an anchor and filled with aqueous fluid

CNS

brain and spinal cord

Cochlea

Cochlea function

spiraling chamber that contains the organ of Corti

Cornea

made up of a fibrous tunic

Cortex

grey matter of cerebellum

Diencephalon

forms the centre core of the forebrain

Dorsal funiculus

Dorsal median sulcus

Dorsal horn

consist of interneurons

Dorsal ramus function

supply forsum of the neck and the posterior trunk

Dorsal ramus

Dorsal root function

contains sensory fibres; cell bodies found in the DRG

Dorsal root

Dura matter function

strong meningeal layer that consists of two layers: periosteal and meningeal

Obturator nerve

Obturator nerve function

innervates adductor muscles: adductor brevis, longus and magnus

Eardrum (tympanic membrane)

Endoneurium

wraps around axon

Epineurium

wraps around nerve

Epithalamus

forms part of the roof of the third ventricle

Exteroceptors

sensitive to stimuli arising from outside the body

Facial nerve

innervates muscles of facial expression; taste to anterior portion of the tongue; motor control to the lacrimal glands, mucus glands, and saliva; and sensory to part of the face and mouth

Femoral nerve function

innervates anterior thigh muscles: sartorius, rectus femoris, vastus lateralis, vastus medialis, and vastus intermedius

femoral nerve

Ascending Fibers

go up to the brain

Descending fibres

go down to the body

commissural fibers

cross the midline

Filiform function

most numerous papillae but do not contain taste buds

Filiform papillae

Foliate function

papillae found on each side of the tongue

Foliate papillae

Foramen magnus

hole where the spinal cord begins

Fourth ventricle

Fungiform function

taste buds found all over the tongue

Fungiform papillae

Glossopharyngeal nerve

innervates structures of the tongue (posterior third for sense of taste) and pharynx

Gluteal nerves function

part of the sacral plexus that innervates the gluteal muscles

Gluteal nerves

Gray commissure

contains the central canal

Gray matter

neuronal cell bodies, dendrites, short unmyelinated neurons

Hypoglossal nerve

runs inferior to tongue and innervates the tongue muscles for movement

Incus

Insula

deep sulcus within the cerebral cortex

Functions of the nervous system

i) sensory receptors monitor changes inside and outside the body

ii) processes and interprets sensory input

iii) dictats a response by activating effector organs

Interneurons

relay signals onto other neurons

Iris

pigmented anterior portion with muscle fibres that surround the pupil

Lacrimal glands

produce tears

Lateral funiculus

Lens

divides the posterior and anterior cavities

Lateral horn

Lateral ventricles

location of CSF production

Lumbar plexus

Malleus

Mandibular branch

Maxillary branch

Median Nerve

Innervates anterior forearm muscles and lateral palm: pronator quadratus and pronator teres; helps with sensation in 3.5 fingers

Meningeal branch

branch of spinal nerves that goes back into the vertebral canal to innervate spinal structures

Musculocutaneous nerve

innervates biceps brachii and brachialis

Nerve plexus

a network of nerves that originate from the ventral rami to serve the limbs

Oculomotor nerve

innervates muscles that open the eyelid, constrict the pupil, and change lens shape when accommodating for near vision (adduction)

Olfactory nerve

sensory nerves of smell that innervate the olfactory mucosa

Cribiform plate of ethnoid bone

Which bone do olfactory nerves cross?

Optic nerve

sensory nerves of vision

Optic chiasm

crossover of the visual nerves

Opthalamic branch

Palprebrae

eyelids

Perineurium

sheath that covers fassicle

Peroneal (common fibular) nerve

Pharyngotympanic tube

Pharyngotympanic tube function

links middle ear to pharynx; is usually closed off but can help relieve pressure

Phrenic nerve

goes to the thoracic cavity; innervates diaphragm

PNS

all peripheral nerves outside of the CNS; neuronal cell bodies = ganglia

Posterior cavity

filled with vitreous humor

Proprioceptors

located in skeletal muscles, tendons, joints, and ligaments to maintain posture