Final Lab Practical

Cranial nerve I

Name: olfactory nerve

Type: sensory

Function(s): smell

Cranial nerve II

Name: optic

Type: sensory

Function: sight

Cranial nerve III

Name: Oculomotor

Type: motor

Function: eyeball and eyelid movement

Cranial nerve IV

Name: trochlear

Type: motor

Function(s): eyeball movement of superior oblique muscle

Cranial nerve V

Name: trigeminal

Type: both

Function(s): 3 branches - ophthalmic, maxillary, mandibular - respond to light touch in these areas or mastication

Cranial nerve VI

Name: abductees

Type: motor

Function(s): eyeball movement of lateral rectus muscle

Cranial nerve VII

Name: facial

Type: both

Functions: taste to anterior portion of tongue, lacrimation, salivation, most facial expressions

Cranial nerve VIII

Name: vestibulocochlear

Type: sensory

Functions: vestibular branch - hearing, cochlear branch - balance and equilibrium

Cranial nerve IX

Name: glossopharyngeal

Type: both

Functions: taste to posterior portion of tongue, senses stretch on carotid body to detect blood pressure

Cranial nerve X

Name: vagus

Type: both

Functions: MOST functions: pharyngeal branch - swallowing and vocalization, carotid branch - sense stretch on heart (heart rate), abdominal branch - stimulates smooth muscle of digestive organs

Cranial nerve XI

Name: accessory

Type: motor

Functions: innervates sternocleidomastoid - contralateral rotation and flexi on of neck and trapezius - extension of neck, elevation of scapula, and retraction of scapula

Cranial nerve XII

Name: hypoglossal

Type: motor

Function: tongue movement

Central nervous system

Brain and spinal cord

Peripheral nervous system

Spinal and cranial nerves

Somatic nervous system

Division of PNS that is under voluntary control

Autonomic nervous system

Division of PNS that is not under conscious control - sympathetic and parasympathetic

Somatic integration centers

Regions of the CNS that synthesize sensory and motor information for decision making

Autonomic integration centers

Synthesize sensory and motor information to maintain autonomic function

Somatic sensory division

Afferent: carries conscious information TO the brain

Somatic motor division

Efferent: carries conscious information FROM the brain to effectors

Visceral division

Autonomic (unconscious) sensory (afferent) information from organs and receptors

Sympathetic nervous system

Responsible for arousal during the fight/flight response

Parasympathetic nervous system

Rest and digest - returns the body to homeostasis following the fight/flight response

Nerve

Bundle of neural axons - take in information from the CNS or effector

Tract

Combination of nerves that take in similar information in large amounts.

\- bidirectional: afferent and efferent

Nuclei

Groups of cell bodies (gray matter) in the CNS that process information for a singular nerve

Ganglia

Group of cell bodies in the PNS that process information for multiple nerves

Microglia

Type of glial cell in CNS that initiates the immune response through phagocytosis

Effectors

Cells that efferent (motor) neurons innervate

\- smooth muscle: autonomic

\- cardiac muscle: autonomic

\- skeletal muscleL somatic

\- glans: autonomic

Schwann cells

Type of glial cell in PNS that produces myelin and aids in axon regeneration (limited)

Astrocytes

Type of glial cell in PNS that helps form the BBB with its perivascular feet, stabilizes blood vessels and capillaries, interneural communication (between neurons)

Satellite cells

Type of glial cell in PNS that surrounds cell bodies to provide support and nutrients

Ependymal cells

Type of glial cell found in the CNS that produces and circulates CSF with its cilia

\- CSF is then filtered in the choroid plexus

Oligodendrocytes

Type of glial cell found in the CNS that produces myelin and aids in axon regeneration

Soma

Cell body of neuron that holds organelles

Axon

Long projection from the cell body that conducts electrical signals

\- can be myelinated or unmyelinated

Dendrites

Short projections that receive information and send it TO the soma

Axon hillock

Cone-shaped region that connects the soma to the axon

\- initiates action potential

Axon collateral

Branch coming off the axon but not at the terminal end

\- connects to other neurons to form networks

Nissl body

Small dots within the soma that are covered in ribosomes and are used for protein synthesis

Nucleus

Found within medial portion of the soma, contains the instructions for protein synthesis

Myelin sheath

Layers of white insulation around the axon that speeds up propagation

Nodes of ranvier

Unmyelinated areas of the axon between neurilemmocytes

\- site of conduction in saltatory conduction

Telodendria

Terminal branches of axon that serve in transmission

Synaptic knob

Distal ends of telodendria that house synaptic vesicles filled with neurotransmitters

Epineurium

Dense connective tissue that surrounds entire nerve

Perineurium

Dense connective tissue that surrounds each fascicle

Endoneurium

Areolar and adipose tissue that surrounds each individual neuron

Fascicle

Circular bundle of nerves similar to a tract

Unipolar

Only 1 projection extends from the soma

\- singular projection splits into a dendrite and telodendrite

Bipolar

1 axon and 1 dendrite extend from the soma, found in the retina

Multipolar

Most common neuronal shape with 1 axon and multiple dendrites, ie. interneurons

Diencephalon

Thalamus, hypothalamus, epithalamus

Brain stem

Midbrain, pons, medulla oblongata

Olfactory bulb and tract

Balloon shaped projections on the anterior portion of the brain that attach to the tract of the way to the cribriform plates (CNI)

Optic nerve

Tubes extending from the optic chiasma (CNII) to the eyeball (anterior to chiasma)

Optic tract

Nerve endings posterior to the optic chiasma (CN II)

Optic chiasma

The X-shaped structure formed at the point below the brain where the two optic nerves cross over each other (CN II)

Pituitary gland

Bean shaped structure inferior to the optic nerve/chiasma that attaches to the hypothalamus via the infundibulum

Mammillary body

Bilateral half-oval shaped structure that hangs inferiorly, superior to the pons

Midbrain

Superior portion of brain stem, posterior to mammillary body

Pons

Middle portion of brain stem that produces anteriorly with ridges

Medulla oblongata

Inferior portion of brain stem that is posterior and inferior to the pons

Gurus

A protuberance on the surface of the brain between sulki

Pre Central gyrus

Anterior to Central sulcus, primary motor cortex

Postcentral gyrus

Posterior to central sulkus, primary somatosensory cortex

Sulkus

Shallow groove in the cerebrum

Longitudinal fissure

Medial groove that separates the left and right cerebral hemispheres

Transverse cerebellar fissure

Deep groove that separates the cerebrum from the cerebellum

Central sulkus

Separates the frontal and parietal lobes

Temporal lobe

Lateral lobe inferior to the parietal

Frontal lobe

Lobe anterior to the central sulcus

Occipital lobe

Posterior lobe on the back of the skull

Insula

Lobe deep to the frontal and temporal lobes

Cerebellum

“Little brain” that is inferior and posterior to the pons, second largest part of the brain

Cerebrum

Superior portion of the brain with en exterior cortex and many internal structures

Corpus collosum

Large commissural tract that connects the cerebral hemispheres allowing for communication

Fornix

Smaller commissural arch inferior to the corpus collosum and lateral ventricle

Lateral ventricle

Space between the corpus collosum and fornix that holds CSF

Septum pellucidum

Thin membrane that separates lateral ventricles, holds CSF in place

Thalamus

Central oval portion of the diencephalon

Hypothalamus

Anterior and inferior to the thalamus, has a groove for the third ventricle

Pineal gland

Gland posterior to the thalamus in the midbrain

Cerebral aqueduct

Tunnel that allows CSF to flow from the third ventricle to the fourth ventricle

Fourth ventricle

Space that holds CSF anterior to the cerebellum

Arbor vitae

Branched white matter within the cerebellum

Spinal cord

Continuous with brain to L1/L2 (lumbar region)

Spinal nerves

Mixed nerves that branch off from the spinal cord exiting from the intervertebral foramen (except for the 1st), named based on the bone segment they originate from

How many spinal nerves are in the thoracic region?

12

How many spinal nerves are in the cervical region?

8

How many spinal nerves are in the sacral region?

5

How many spinal nerves are in the lumber region?

5

How many spinal nerves are in the coccyx?

1

Central canal

Tunnel at the center of the spinal cord that houses CSF

Anterior median fissure

Deep groove along that anterior surface of the midline

Posterior median sulcus

More superficial groove along the posterior surface of the midline

White matter

Exterior portion of the spinal cord

Gray matter

Interior portion of the spinal cord that resembles a butterfly

Ventral (anterior) horn

Ridge of anterior gray matter

Dorsal (posterior) horn

Posterior ridge of gray matter