anatomy exam 1

1.Vertebral foramen

2.Vertebral Canal

1. The space in the middle the vertebra.

2. The summation of all of these is the _____.

1. cervical enlargement

2. lumbar enlargement

1. widening of the spinal cord near the head

2. widening of spinal cord near lower back

larger because more cell bodies.

intervertebral foramina

lateral opening between adjacent vertebra

conus medularis

contains the sacral and coccygeal segments of spinal cord, where the cord ends

cauda equina

resembles horse tail

Filum terminale

extension/continuation of pia mater, anchors spinal cord within vertebral canal

Meninges

cover and protect the brain and spinal cord

dura mater

Outer most meninge, lines of periosteum of the skull, and protects the brain

epidural space

a fat-rich cushioning space just external to the dura mater

arachnoid mater

weblike middle layer of the three meninges

(lower than the arrow)

subarachnoid space

a space in the meninges beneath the arachnoid membrane and above the pia mater that contains the cerebrospinal fluid

pia mater

Innermost layer of the meninges with direct contact with spinal cord

denticulate ligaments

extensions of pia mater that secure cord to dura mater

1. dorsal horn

2. ventral horn

3. lateral horn

1. contains interneurons

2. • 3. contain motor neurons

anterior median fissure

wide, deep crease along the ventral surface of the spinal cord

central canal

A tiny channel found within the spinal cord and inferior medulla oblongata

spinal nerve

combination of the dorsal root and ventral root

Dermatome

skin segments corresponding to spinal nerves

dorsal root

dorsal root ganglion

only sensory neurons entering the dorsal horn

the bulb on the root, created by sensory neuron cell bodies, cell body in middle of length

ventral root

contains only axons of motor neurons

1. Somatic motor

2. visceral motor

3. somatic sensory

4. visceral sensory

1. control of skeletal muscles (ventral horn)

2. control of smooth muscles and glands (lateral horn)

3. sensation from skin, skeletal muscles, joints (dorsal horn)

4. sensation from the viscera (between dorsal and lateral)

ascending pathway (3 neurons)

spinothalamic tract

1. source to dorsal horn

2. interneuron decussates to contralateral side into white matter, then to thalamus

3. to cerebral cortex

can be shared w visceral neurons, which is why visceral pain can feel like it has a somatic origin

descending pathway (2 neurons)

corticospinal tract

1. upper motor neuron (interneuron of CNS) down to white matter

2. decussation in medulla

3. synapse in ventral horn

4. lower motor neuron innvervate skeletal muscles

Spinal Reflexes

Polysynaptic (2 neurons + interneuron)

Monosynaptic (2 neurons)

Involuntary and stereotyped reactions

1+ neurons required; stimulus travels along a sensory neuron that synapses with 1+ interneurons in the dorsal horn. withdrawal/pain reflex example.

sensory neuron synapses directly with motor neuron in ventral horn; no inter-neurons needed

dorsal ramus

somatic motor and somatic sensory to posterior body wall

ventral ramus

carries somatic motor and somatic sensory to the lateral and anterior body wall

communicating rami

carry visceral motor (sympathetic) and visceral sensory neurons to and from the sympathetic chain

sympathetic chain ganglia

have a second cell body for the sympathetic nervous system, first is in lateral horn of T1-L2

Sympathetic Chain

distributes innervation to viscera

intercostal nerves

send small branches to the nearby muscles, bones, and skin

brachial plexus

C5-T1

lumbosacral plexus

Formed of L2-S4 rami. Supplies the lower limb.

neural tube

where brain and spinal cord are formed 4 weeks after conception, forms glial cells

interventricular foramen

connect lateral ventricles to third ventricle

falx (sickle) cerebri

separates the two cerebral hemispheres

superior sagittal sinus

large sinus

tentorium cerebelli

second fold in brain, inside transverse fissure

transverse fissure

separates cerebrum from cerebellum

Diencephalon

thalamus, hypothalamus, epithalamus

midbrain

A small part of the brain above the pons that integrates sensory information and relays it upward.

pons

tracts of white matter, has cerebellar peduncles

medulla oblongata

Part of the brainstem that controls vital life-sustaining functions such as heartbeat, breathing, blood pressure, and digestion.

(CAR)

Cerebellum

A large structure of the hindbrain that controls fine motor skills. "little brain)

info from body = info on position

info from brain = tells it the cerebrum is going to initiate movement

arbor vitae

"Tree of life"; white matter of the cerebellum

choroid plexus

produces CSF, found in walls of ventricles

septum pellucidum

thin membrane that separates lateral ventricles

third ventricle

the ventricle located in the center of the diencephalon

cerebral aqueduct

connects the third and fourth ventricles

fourth ventricle

the ventricle located between the cerebellum and the dorsal pons,

arachnoid granulations

penetrate dural venous sinuses

dural sinuses

spaces that collect blood that has circulated through the brain

longitudinal fissure

separates cerebral hemispheres

central sulcus

separates frontal and parietal lobes

lateral sulcus

Separates temporal lobe from parietal and frontal lobes

Lateral Sulcus

Separates temporal lobe from parietal and frontal lobes

parieto-occipital sulcus

divides parietal and occipital lobes

precentral gyrus

primary motor cortex

postcentral gyrus

primary somatosensory cortex

insular lobe

The lobe tucked away in the lateral sulcus.

gustatory taste cortex

commisural fibers

connect hemisphere's cortexes by crossing the corpus callosum