Block 1 Lecture exam

Anterior/posterior

front and back

Superior/inferior

above and below

Proximal/distal

closer to and farther from the origin

Rostral/caudal

toward the nose and tail

Astrocytes

- Most abundant glial cell

- health and regulation of brain

- CNS

Microglia

- smallest/least abundant glial cells

- brain immunity

- CNS

Ependymal cells

- produce cerebrospinal fluid

- CNS

Oligondendrocytes

- produce myelin sheaths

- CNS

Satellite cells

- surround neuron cell bodies within ganglia

- PNS

Schwann cells

- produce myelin sheath

- PNS

CNS neuroglia

astrocytes, microglia, ependymal cells, oligodendrocytes

PNS neuroglia

satellite cells and Schwann cells

Organizational structure of skeletal muscle

muscle -> fascicle -> muscle fiber

Epimysium

surrounds entire muscle

Perimysium

surrounds fascicle

Endomysium

surrounds muscle fiber

Ossification

bone formation

Intramembranous ossification

- direct ossification

- ~5-6 weeks of development

- forms flat bones, skull, mandible

Endochondral ossification

- indirect ossification

- late second month of development

- forms all other bones

Compact bone

- dense, outer layer of bone

- organized by osteons

Spongy bone

- porous, inner layer of bone

- organized by trabeculae

Osteons

- bullseye like structures in compact bone

- provide rigidity and flexibility

- contain osteoblasts and osteocytes

Trabeculae

- flat plates within spongy bone

- where RBM is found

Calcitonin

- secreted by thyroid gland

- decreases osteoclast activity

- decreases blood calcium concentration

- builds bone

Osteoporosis

- Usually seen in post-menopausal women

- osteoclast activity > osteoblast activity

Osteomalacia

inadequate bone mineralization

Osteosarcoma

bone cancer

Arthritis

inflammation of a joint

Artherosclerosis

- narrowing of the arteries

- lipid deposition within artery wall

- improper blood flow

Lymph node

tissue that utilizes lymphocytes to filter blood

Sentinel node

first lymph node to receive lymph

Paired bones of the skull (8)

parietal, temporal, maxillae, zygomatic, nasal, lacrimal, palatine, nasal conchae

Unpaired bones of the skull (6)

frontal, occipital, sphenoid, ethmoid, mandible, vomer

Meninges function

- Cover and protect CNS

- Contain CSF

Meninges layers

Dura mater - outer layer

Arachnoid mater - middle layer

Pia mater - inner layer

Cerebrospinal fluid

Fluid in subarachnoid space

Produced by choroid plexus

Flow of CSF

1.) Produced in choroid plexus

2.) Flows into subarachnoid space

3.) Diffusion occurs

4.) More CSF produced

5.) More CSF pushed into blood through sagittal sinuses

Choroid plexus

- Located between the 3rd and 4th ventricles

- Secretes CSF through ependymal cells

Hydrocephalus

- Overproduction of CSF or decreased resorption

- Treated with shunt

Meningitis

- Inflammation of the meninges

- diagnosed by collected CSF by lumbar puncture

- Treated by antibiotics

Brain tumors

- can grow in several locations

- symptoms depend on size and location

- do not metastasize

How could facial artery be involved in development of meningitis?

Facial vein drains into the cavernous sinus, located next to the meninges

CN I

Olfactory; sense of smell

CN II

Optic; sense of sight

CN III

Oculomotor; eye movement

CN IV

Trochlear; eye movement

CN V

Trigeminal; sense of touch to face

3 branches: ophthalmic (V1), maxillary (V2), and mandibular (V3)

CN VI

Abducens; eye movement

CN VII

Facial; mimetic muscle movement, salivary glands and taste

CN VIII

Vestibulocochlear nerve; sense of hearing and balance

CN IX

Glossopharyngeal; tongue and pharynx movement and sense of taste

CN X

Vagus; gut brain axis

CN XI

Accessory; movement of neck muscles

CN XII

Hypoglossal; tongue movement

Mimetic muscles of forehead (1)

epicranius (frontal and occipital)

Mimetic muscles of eyelid (2)

Orbicularis oculi

Currugator supercilli

Mimetic muscles of mouth (11)

Orbicularis oris

Buccinator

Zygomaticus major

Zygomaticus minor

Risorius

Levator labii superioris

Levator anguli oris

Depressor labii inferioris

Depressor anguli oris

Mentalis

Platysma

TMJ Disorder

-Umbrella term for acute or chronic pain in mastication muscles or the temporomandibular joint

-Symptoms: head pain, eye/mouth/ear problems, neck/jaw problems

Location and innervations of the salivary glands

- Parotid gland: inferior to ear; CN VII

- Sublingual gland: below tongue; CN VII

- Submandibular: below mandible; CN VII

What is the sensory innervation of the face?

Trigeminal nerve (CN V)

Eye orbit bones (7)

Frontal, sphenoid, zygomatic, maxillary, palatine, lacrimal, ethmoid

Lacrimal apparatus

- Structures that produce, store, and remove tears

- located superolateral/anterolateral

Names, locations, and innervations of the extraocular muscles

Superior rectus

Location: superior to eyeball

innervation: CN III

Medial rectus

Location: medial eyeball

Innervation CN III

Inferior rectus

Location: inferior eyeball

Innervation: CN III

Lateral rectus

Location: distal eyeball

Innervation CN VI

Superior oblique

Location: superior eyeball

Innervation: CN IV

Inferior oblique

Location: inferior eyeball

Innervation: CN III

Structures of the external eye

Cornea, lens, optic nerve

Structures of the anterior eye chamber

aqueous humor

Structures of the posterior eye chamber

aqueous humor

Layers of the eye wall

Retina, choroid, sclera

Horner's syndrome

Symptoms: miosis (constricted pupil), partial ptosis (droopy eyelid), loss of hemifacial sweating

Cause: damage to pre and post sympathetic fibers of face

Direct and consensual light reflex

constriction of ipsilateral and contralateral

pupil when a light is shone into one eye. It shows the function of CN III and also the

optic pathway. These reflexes may be lost in head trauma etc.

Pupillary dilation due to CNIII palsy may be due to tumors, aneurysms...

Gluacoma

Impaired drainage of aqueous humor

Increased intraocular pressure and retinal blood flow

Causes optic neuropathy, ganglion cell loss, blindness

Cataracts

Degeneration and opacity of the lens

Impaired vision and blindness

Caused by deposition of aggregated proteins

Names, locations, and innervations of muscles of mastication

Masseter

Location: zygomatic arch

Innervation: CN V3

Temporalis

Location: temporal fossa

Innervation: CN V3

Lateral pterygoid

Location: lateral pterygoid process

Innervation: CN V

Medial pterygoid

Location: medial pterygoid process

Innervation: CN V

Locations and functions of the paranasal sinuses

Frontal sinus

Location: frontal bone

Ethmoidal air cells

Location: ethmoidal labyrinth between orbit and nasal cavities

Sphenoidal sinus

Locations: sphenoid bone

Maxillary sinus

Location: maxilla; largest sinus

Functions: purify, moisten, and warm/cool air; sound resonance; make head lighter

Contents of middle ear

malleus, incus, stapes

Contents of inner ear

cochlea, vestibule, semicircular canals

Location, innervation, and function of the tensor tympani muscle

Location: handle of malleus

Innervation: CN V

Function: tenses tympanic membrane

Location, innervation, and function of stapedius muscle

Location: stapes

Innervation: CN VII

Function: dampens sound

Hyperacusis

Symptoms: Excessively sensitive hearing

Cause: Loss of stapedius muscle function from facial nerve paralysis

Otitis externa

Symptoms: inflammation of the outer ear

Significance: lesions within canal may cause nausea or vomiting; in eldery, cardiac arrest

Chronic otitis media

Symptoms: severe/chronic infection of middle ear

Significance: often seen in children

Myringotomy

-Incision made through the tympanic membrane

-Tube inserted for drainage

-ONLY USED TO TREAT OTITIS MEDIA

Organ of balance

vestibular apparatus

Organ of hearing

organ of corti

Cleft palate

-Failure of fusion of palatine processes

-Anterior/posterior possible

-Surgery required

Cleft lip

-Failure of fusion of maxillary and nasal processes

-Unilateral/bilateral possible

-Surgery required

Most common congenital malformation of head

Unilateral cleft lip

Location and innervation of sternocleidomastoid

Location: sternum/clavicle --> mastoid process

Innervation: CN XI

Names, location, and innervation of the infrahyoid muscles

Names: TOSS: thyrohyoid, omohyoid, sternohyoid, sternothyroid

Locations: below hyoid bone

Innervation: cervical ansa

Names, location, and innervation of the suprahyoid muscles

Names:

-mylohyoid (CN V)

-stylohyoid (CN VII)

-anterior/posterior digastric muscles (CN V/CN VII)

-geniohyoid (CN XII)

Location: above hyoid bone

Location and innervation of the genioglossus muscle

Location: below tongue

Innervation: CN XII

Location and innervation of the styloglossus muscle

Location: styloid process

Innervation: CN XII

Location and innervation of the hyoglossus muscle

Location: hyoid bone

Innervation: CN XII

Location, function, and hormones produced by the thyroid gland

Location: C5-T1

Hormones:

1. Thyroxin - controls metabolism

2. Calcitonin - calcium metabolism

Location, function, and hormones produced by the parathyroid gland

Location: external to thryroid capsule and internal to connective tissue sheath

Hormones:

1. Parathyroid hormone - stimulates osteoclast activity

Name, function, and location of the rectus capitus

Location: C1 of cervical plexus

Function: flexes head

Name, function, and location of the longus capitus

Location: C1-C4 of cervical plexus

Function: bends head forward, turns head sideways

Name, function, and location of the longus colli

Location: C2-C8 of cervical plexus

Function: bends and turns cervical column

Blood supply and drainage of head and neck

Supply: vertebral arteries and the common carotid arteries

-forms the circle of Willis in the brain

-for superficial blood supply the external carotid artery brings blood to the facial artery

-facial vein drains the blood from the face

-all drain into the internal jugular vein