Anatomy 3300 OSU Unit 4

Name the paranasal sinuses

Frontal, Ethmoid, Sphenoid, Maxillary

Hard palate is formed by

1. Palatine processes of maxillae

2. Horizontal Plates of palatine bones

Bones of Orbit

1.Frontal

2.Zygomatic

3.Maxillary

4.Sphenoid

5.Ethmoid

6.Lacrimal

7.Palatine

Vomer creates

bone seen in nasal cavity under perpendicular plate

Nasal Septum is made of

1.Perpendicular plate of the ethmoid bone

2.Vomer bone

3.Septal cartilage

The ____________ enters the mandibular foramen and exits the metal foramen as the ______________

inferior alveolar n

mental n

What primary germ layer creates nervous system?

Ectoderm

Neurulation week 3..name the four steps

1.Formation of neural plate

2.Shaping of neural plate

3.Invagination of neural plate

4.Closure of neural groove•

Forms the neural tube &neural canal

Neural tube creates

Spinal cord and brain

Neural canal creates

Ventricular system and central canal of spinal cord

Proencehphalon gives

Telen and Dien

Mesencephalon gives

Mesen

Rhombencephalon gives

Meten and Myelen

Telen makes

Cerebrum and turns into lateral ventricles

Dien makes

Thalamus, hypothalamus, and epithalamus and turns into third ventricle

Mesen makes

Midbrain and turns into cerebral aqueduct

Meten makes

pons and cerebellum and turns into fourth ventricle

Myelen makes

medulla oblongata and makes fourth ventricle

White matter is made of

myelinated axons

Gray matter is made of

neuronal cell bodies, dendrites, unmyelinated axons, neuroglia

Main functions of cerebral cortex

Conscious thought, speech, personality, voluntary movement, sensory input

split into motor, sensory, and association

(gray matter)

Post Central Gyrus (# and function)

1,2,3

Primary general sensory area

Pre central Gyrus (# and function)

4

Primary motor area

"fine motor"

Occipital lobe (# and function)

17, 18

Primary and secondary visual reception area

Temporal Lobe (# and function)

41, 42

Primary and secondary auditory reception area

Frontal Lobe (dom hemisphere only) (# and function)

44, 45

Broca's area

Motor speech area

Frontal lobe, prefrontal cortex (# and function)

9,10,11

Personality and character traits

Commissural fibers

connect gray areas between two hemispheres

(corpus callosum)

Association fibers

connect parts of same hemisphere

Projection fibers

connect cerebral cortex to to other parts of CNS (like spinal tracts)

Basal Nuclei, give examples and function

-nerve cell bodies deep in cerebrum:

- caudate nucleus, putamen, globus pallidus

- regulate initiation and termination of movement, Inhibits extraneous muscle contraction and helps to maintain motor control

Damage to basal nuclei can lead to

Parkinsons and huntingtons disease

Function of Thalamus

Major relay center for all sensation entering the cerebral cortex EXCEPT olfaction. Aids in motor activity

Function of Hypothalamus

Major regulator of the body's internal environment, through the autonomic, limbic and endocrine systems

Function of Epithalamus

Helps to regulate sleep-wake cycle with the hypothalamus (main projection is the pineal body, which secretes the hormone melatonin)

Midbrain projections, nerves, etc

1) cerebral peduncles (ventral surface)

2) superior colliculi (dorsal surface)

3) inferior colliculi (dorsal surface)

Located in the white matter are pigmented nuclei:

1) substantia nigra(degenerated in Parkinson's disease)

Associated Cranial Nerve Nuclei:

1) Oculomotor (III)

2) Trochlear (IV)

Pons CN and what it is conduction tracts for

Major component of pons are conduction tracts that course between:

1) higher brain centers and the spinal cord

2) motor cortex and cerebellum

Associated Cranial Nerve Nuclei

V - VIII

Medulla Oblongata Function and Projections and CN

Role: autonomic reflex center housing important visceral motor nuclei (ex. cardiovascular and respiratory centers)

Projections/Budges from medulla oblongata:

1)Pyramids (ventral surface)

2)Gracile tubercle (dorsal surface)

3)Cuneate tubercle (dorsal surface)

Associated Cranial Nerve Nuclei:

VIII - XII

Cerebellum Functions

provides timing and patterns of skeletal muscle contractions for smooth and coordinated movements; also provides error correcting feedback for movements.

Functions of Cerebrospinal Fluid

-Serves as a shock absorber

-Helps in the transport nutrients and removal of waste

-Helps maintain the proper ion balance in neural tissue

Vertebral Arteries branch off of ______ and flow to the ______ part of the brain

- subclavian arteries

-posterior

Internal Carotid arteries branch off _________ and circulates through the _____ part of the brain

- common carotid

- anterior

Circle of Willis is composed of

-Anterior communicating a

-Anterior cerebral aa.

-Internal carotid aa.

-Posterior communicating aa.

-Posterior cerebral aa.

Anterior cerebral a is a terminal branch off

internal carotid

Anterior cerebral supplies most of the

medial and superior (more frontal and parietal)

Middle Cerebral supplies

lateral surface of hemispheres, passes through temporal and frontal lobes

Posterior Cerebral supplies

inferior portion of hemispheres (mostly temporal and all of occipital)

Fibrous Tunic

sclera

cornea

vascular tunic

iris

ciliary body

choroid

retina

pigmented layer

neural layer

Parasympathetic stimulation causes

circular muscles to contract

(smaller pupils)

Sympathetic stimulation causes

radial muscles to contract (dilation)

At the optic chiasma, fibers from ___________ cross over

nasal aspect

When smells go to the Primary Olfactory complex in the temporal lobe,

they are connected with the orbitofrontal complex to identify and discriminate odors

When smells go to the Subcortical route to the hypothalamus, amygdala, and limbic system,

They evoke responses like emotion and memory by smells

Muscles of facial expression (inn by facial n)

frontalis

occipitals

orbicularis oculi

orbicularis oris

buccinator

platysma

5 motor branches of facial nerve

temporal

zygomatic

buccal

marginal mandibular

cervical

Muscles of mastication (inn by mandibular division of trigeminal)

masseter - elevate

temporalis - elevate and retract mandible

medial pterygoid - elevates, protracts, side to side

lateral pterygoid - depresses mandible, protracts, side to side

Muscles that elevate hyoid bone

mylohyoid

digastric

stylohyoid

geniohyoid

Muscles that depress hyoid

sternohyoid

omohyoid

sternothyroid

thyhyoid

Venous drainage from head and neck

ext jugular >

subclavian and internal jugular >

brachiocephalic >

superior vena cava>

right atrium

Motor neurons are in

ventral horns

Sensory neurons are in

dorsal root ganglia

Motor neurons travel from

exit spinal cord through ventral root > spinal n. > ventral OR dorsal ramus > through named nerves to effector

Sensory neurons travel from

Axons from peripheral receptors of sensory neurons enter through dorsal OR ventral rams > spinal n. > dorsal root > synapse with interneuron in dorsal horn

Neurons of sensory tract

from dorsal root ganglion ->

cross over to contralateral side after synapsing in medulla ->

synapse in thalamus-> post central gyrus

Dorsal Column system carries

general sensory info from body to post central gyrus like touch, vibration, pressure, weight, two point discrimination

Fasciculus gracilis (of dorsal portion)

-axons from LL and lower trunk

- sensory info from below T6

Fascicles cuneatus

-axons from UL and upper trunk

- sensory info from T6 and up

Lateral Spinothalamic Tract carries

pain and temperature

Lateral Spinothalamic

•3º neuron in the thalamus

•Axons from the thalamus carries information the postcentral gyrus

•2º neuron in the dorsal horn

•Axons cross over within 1-2 spinal segments to the contralateral side of the cord and ascend

•1º neuron in the dorsal root ganglion

•Synapses in the dorsal horn of the spinal cord IMMEDIATELY upon entering the cord

Lateral Corticospinal Tract

•Originates at the precentralgyrus

•1º neuron in the precentralgyrus, referred to as Upper Motor Neurons (UMN)

•Axons travel within the pyramids of the medulla on the same side, then cross over to the opposite side just above the spinal cord (pyramidal decussation)

•2º neuron in the ventral horn of gray matter, referred to as Lower Motor Neurons (LMN)

•Axons from this neuron run through the ventral roots, spinal nerves and dorsal and ventral rami to peripheral muscles