Anatomy and Physiology chapter 11

What two major organs make up the central nervous system?

brain and spinal cord

What is white matter? What is gray matter?

Areas consisting of myelinated axons

cells bodies

Where is white/gray matter located in the brain versus the spinal cord?

Brain White- inner core

Brain Grey- Outer layer or the cortex

Spinal cord white- outer tracts

Spinal cord Grey- Center

Describe each layer of the meninges of the brain. Include location and any special features.

outer- dura mater, tough

Arachnoid mater- web-like

Pia mater- thin, has blood vessels and nerves

What is a dural sinus? Be precise in describing its contents.

Space in the dura that carries venous blood

What tissues are found in the epidural space?

adipose tissue, blood vessels, and loose CT

What is a subdural hematoma? Be precise in describing the location.

Accumulation of blood between the dura and archnoid mater

What structures are affected by meningitis? Why is it dangerous?

Arachnoid and pia

swelling can cause severe damage to brain

What does cerebral spinal fluid (CSF) look like?

clear, water, fluid

Describe where each of the ventricles of the brain is located. What is their collective

function?

2 lateral- first and second ventricles are within the cerebral hemisphere

third ventricle- surrounds diencephalon

Fourth ventricle- within brainstem anterior to cerebellum

What is the cerebral aqueduct?

Connects third and fourth ventricles

Where are the choroid plexuses located? What do they make?

Ventricles and part of the pia mater

CSF

Which cells make cerebral spinal fluid?

ependymal cells

What are the functions of cerebral spinal fluid?

nutritive, protective, and helps maintain stable ionic concentrations

Describe the circulation of cerebral spinal fluid. Be sure to include where is made and where

it is reabsorbed

made in the choroid plexuses and circulates through the ventricles and cerebral aqueduct and reabsorbed by the arachnoid granulation within the dural sinuses

List the parts of the embryonic brain and indicate which mature brain part each becomes.

Forebrain becomes cerebrum, basal nuclei, and diencephalon

Midbrain remains as the midbrain

Hindbrain becomes cerebellum, pons, and medulla oblongata

What are the anatomical terms for the grooves of the cerebrum vs the ridges?

Grooves- Sulci

Ridges- Gyri

What is the difference between a sulci and a fissure?

Fissures are deeper

What is the function of the corpus collosum?

Connects cerebral hemisphere and allows communication between them

Describe the cerebral cortex.

Thin layer of brain matter, outer most, contains 75% of neuron cell bodies

What is a cerebral vascular accident? What is another name for it in laymen’s terms?

Stroke, ruptured blood vessel

What is meant by sensory, association, and motor area of the brain?

Sensory- areas that interpret your sense

Motor- voluntary muscles, movement secretion

Association- something that interprets complex processes.

Distinguish between the precentral gyrus and postcentral gyrus. Include function and location

(including brain lobe).

Post central- interprets sensations of skin (touch and pressure), parietal lobe'

Precentral- Motor, frontal lobe, control voluntary muscles

What is the effect of sensory nerve fibers crossing over?

Right interprets sensation from the left and vice versa

What are pyramidal cells? Location/function

Large triangular motor neurons that start voluntary movement, initiate motor signals, located in the forebrain, hippocampus, cerebral cortex, and amygdala.

Which parts of the brain are involved in speech? Which components of speech does each

control?

Wernicke’s- plan and understand speech

Broca’s- command action of muscles to produce sound.

List the lobes of the brain and their major functions.

Frontal- intellect, concentration, planning, judgement, and problem solving

Parietal- Sensory areas, skin, speech, expression

Temporal- Hearing, interpret, music, patterns

Occipital- vision

Insula- Taste, emotional responses

What is a dominant hemisphere? Which one is dominant in most people?

Dominant- controls language, verbal, analytics, and computational skills

Left

Distinguish between short-term and long-term memory formation.

Short- Neurons in circuit are circulation over and over, memory gets lost

Long- Change in structure of functions of neurons, makes new synaptic, increase in neurotransmitter release.

Which part of the brain assigns value to a memory?

Amygdala

Where are basal nuclei/ganglia located and what is their function?

Deep in cerebral hemisphere, help control voluntary movement

Which disease is caused by a lack or decline of a neurotransmitter normally secreted from the

basal nuclei/ganglia? Which neurotransmitter is involved?

Parkinsons

Dopamine

Which organ is attached to the hypothalamus via the infundibulum? Which body system does

it belong to?

Pituitary gland

Endocrine

What is are the thalamus and hypothalamus called collectively?

Diencephalon

What is the limbic system?

Several structures in the brain, controls emotional responses, feelings, behavior toward survival

What structure determines wakefulness of the cerebral cortex? What happens if this is

damaged?

Reticular formation, unconsciousness, coma

Distinguish between REM and non-REM sleep.

REM- Rapid eye movement, eyes moving, brain active, dream, memories form, consolidation

Non-Rem- Restful

During which stage of sleep are vital signs decreased vs increased?

Non-Rem

Rem

During which stage of sleep do we dream vs not dream?

Rem

Non-Rem

Where is the arbor vitae located?

Inner core of the cerebellum

List the parts of the brain and their major functions.

Cerebrum- higher brain functions, sensory and motor centers, reasoning, intelligence, personality, memory

Basal nuclei- help voluntary movement

Diencephalon- thalamus; sends sensory info to cerebrum/ hypothalamus; maintains homeostasis

Brain stem- midbrain; reflexes of eyes and head/ Pons; breathing regulation/ Medulla; heart rate, blood pressure, breathing, non-vital reflexes

Cerebellum- Coordination and muscle memory

What are the four brain waves and when is each most prevalent?

Alpha- awake, resting, eyes closed

Beta- Active mental activity, under tension

Theta- mostly in children in some adults during sleep or stress

Delta- mainly during sleep

What are the 5 regions of the spinal cord? How many pairs of spinal nerves arise from each

region?

Cervical- 8

Thoracic- 12

Lumbar-5

Sacral- 5

Coccygeal- 1

What are the structural components of the gray matter of the spinal cord called? Those of the

white matter?

Gray matter- horns

White matter- funiculi

What is the main cell type found in the gray matter of the spinal cord? What is found in the

white matter?

Gray- interneurons

White- micorglia

Describe the cauda equina.

Lumbar and sacral nerves that extend below the spinal cord and the vertebral canal

Why are certain parts of the spinal cord enlarged? Which enlargement serves which general

body part?

They have more axons entering and leaving those locations

Cervical enlargement is upper limbs and lumbar lower limbs

What are the two main functions of the spinal cord?

Spinal reflexes and for impulses to and from the brain

List the components of a reflex arc in the correct order

Receptor, sensory neuron, interneuron, motor neuron, effector

What is the simplest pathway from a sensory receptor to an effector called?

Reflex arc

Describe the three types of spinal reflexes. Include examples to help you remember them

Monosynaptic- knee jerk

Withdrawal- touches or steps on something painful

Cross extensor- step on tack but didn’t fall down

What kind of spinal cord tract (ascending or descending) are associated with sensory vs

motor impulses?

Ascending- sensory

Descending- motor

List the various tracts of the spinal cord and indicate where each tract carries impulses

(fromto)

Spinothalamic- Spinal cord to thalamus

Spinocerebellar- Spinal cord to cerebellum

Corticospinal- cerebral cortex to spinal cord

Reticulospinal- reticular formation to the spinal cord

What is decussation? How does decussation affect the result of certain spinal injuries and

brain injuries?

crossing over of nerve fibers

The brain is damaged on one side it results in loss of sensation or motor function on opposite sides

Are all spinal nerves mixed nerves?

no

Distinguish between the anterior root and posterior root of a spinal nerve.

anterior- motor

Posterior- sensory

What is located in a posterior(dorsal) root ganglion?

cell bodies of sensory neurons

Which ramus (branch) of a spinal nerve becomes a peripheral nerve?

Anterior ramus

Distinguish between the somatic and autonomic nervous systems. Include which general

body parts are served by each

Somatic- Voluntary, muscles, and skin

Autonomic- Involuntary, organs

Describe the connective tissue layers of a peripheral nerve and what each surrounds

Endoneurium- surrounds axon

Perineurium- surrounds bundles of neurons called a fascicle

Epineurium- surrounds a group of fascicles called

Distinguish between sensory, motor, and mixed nerves.

Sensory- into brain or spinal cord

Motor- brain to muscles or glands

Mixed- both sensory and motor nerve fibers, most nerves are mixed nerve

What is the difference between a spinal and cranial nerve?

Spinal nerve from spinal cord

Cranial nerve from brain

Which three cranial nerves move the eyes?

Oculomotor, trochlear, abducens

Which three cranial nerves are entirely sensory with no motor component?

olfactory, optic, vestibulocochlear

Which two cranial nerves serve the tongue?

Glossopharyngeal, hypoglossal

Which cranial nerve serves almost all viscera (organs)?

Vagus

Which cranial nerve is involved in both hearing and balance?

vestibulocochlear

Distinguish between anterior and posterior roots of the spinal cord regarding sensory/motor

impulses.

Anterior- motor

Posterior- Sensory

Describe the type of nerve fibers found in spinal nerves

Mixed nerves part of the axons are sensory going into the spinal cord and part are motor going out of the spinal cord

What is a dermatome? How can it be used clinically?

An area of skin innervated by the spinal nerve

No feeling ina dermatome indicates damage to the associated spinal nerve

What is a plexus? List the nerve plexuses and the general location each serves

Network formed by mixing of spinal nerves going to a particular area

Cervical- neck

Brachial- arm

Lumbosacral-leg

Which spinal nerves are not part of plexus? Why?

Thoracic because each serves a single strip of muscles/skin around one rib

Distinguish between the sympathetic and parasympathetic nervous system. When is each

most active? How does their structure differ?

Sympathetic- Stressful, emergency situation, fight or flight, thoracolumbar division, ganglia in the chains right next to the spinal cord, next to the spinal cord

Parasympathetic- resting, non-stressful conditions, rest and digest, ganglia are next to the organ, cranial sacral,

How are motor pathways of the autonomic nervous system different from those of the

somatic nervous system?

Somatic- voluntary, no ganglions, one neuron cell body in the CNS

Autonomic- involuntary, have ganglion, two neuron, have preganglionic in CNS, post ganglionic neuron

What is sympathetic tone? Why is it important?

Maintains vessel walls and partially contracted

Maintain your blood pressure

What are the general types and subtypes of autonomic neurotransmitters?

What type of nerve fibers are adrenergic vs cholinergic? What does adrenergic and

cholinergic refer to?

What are the two types of cholinergic receptors? How are they similar? How do they differ?

What happens to the nervous system with age?

What are the major characteristics of the following diseases of the nervous system?

Alzheimer’s

Parkinson’s

Amyotrophic lateral scoliosis

Multiple sclerosis