A&P Test2

The neurons of the CNS are located where?

Brain and spinal cord

Know the difference between an afferent and efferent neuron.

Afferent- same as sensory neuron, Carry receptors from the body toward the CNS

efferent- motor neuron goes from nervous system (brain or spinal cord) out into effector (muscle or gland)

What are the 6 neuroglial?  Know their respective functions?

1. Astrocytes

2. Oligodendrocytes

3. Microglial cells

4. Ependymal cells

5. Shwann cell

6. Satellite cell

What are astrocytes

They are neuroglial cell in the cns

1. Help with maintain proper sodium + potassium levels

2. Metabolize old neuro transmitter substance

3. Part of blood brain barrier

What are oligodendrocytes

Cell that militates axon in the cns so in brain/ spinal cord

What are microglial cells

Phagocytitic cells (phagocytes eat things in the cns)

What are ependymal cells

Involved with secretion of cerebral spinal fluid

Schwann cell

Myelinated axon in the pns , counter part to ogliodendrocytes

What is a satellite cell

Support cell bodies in structures called ganglia

What is the structural part of a neuron and their function?

Cell body, axon, dendrites

What are dendrites ?

1. Fine branch tapered structure that attached to the cell body.

2. Will convey nerve impulses toward the cell body

What is the cell body ?

1. Mission Control center for the cell (ribosomes, nucleus,

2. All cells are coordinated and controlled by the cell body

What is an axon?

Pulls nerve Impulses away from the body

how does impulse move along a neuron (i.e. - which direction they travel)

Across dendrites, into cell body, across the cell body, and down the axon

Know the difference between multi, bi and unipolar neurons and where each is found

multi- neurons that have several dendrites + one axon

found everywhere- heart, brain, spinal cord fiber

Bi- one axon one dendrite attached to the cell body (touching) —-0——

found- vision, smell, hearing

Uni- process comes off cell body and splits and one end is a axon and one end is a dendrite, they are peripheral neuron

found- peripheral neuron

Know the definition of a stimulus.

Any change in the external or internal environment

what causes a cell to be polarized [which electrolytes create the R.M.P.]

1. Unequal distribution of sodium and potassium. Salts have to be right

describe the all-or-none principle.

If the stimulus is strong enough to reach the threshold a complete nerve firing occurs

If enough sodium leaks into the cell from -77-55

Know the most common neurotransmitter

Acetylcholine, example there are others gabba dopamine

Differentiate between continuous and saltatory conduction, and where each occurs

Continuous- nerve impulse wave of depolarization and a continuous depolarization throughout the entire membrane of a neurons

Found- unmylinated structures

Saltatory- jumping from one node of ronviere

Found- only in myelinated axons

Which one is more faster continuous or saltatory

Saltatory

What three factors that influence nerve impulse conduction?

1. If the structure is myelinated or unmyelinated (If it’s myelinated it’s faster if it’s unmyelinated it’s slower )

2. Diameter of axon (larger- faster, Smaller- slower)

3. Temperature ( if a neuron is warm it’s faster and if it’s old it’s slower and won’t send impulses bc it’s numb )

Know the difference between types A, B, & C nerve fibers.

Type A- large myelinated fibers with speeds up to 130mphs

Type b- myelinated medium size in diameter and will send impulses at 15 mphs

Type c- small diameter unmyelinated and operate in speed of .5-2 mobs

Differentiate between slow axonal vs. fast axonal transport

Both are mechanism to move materials in the neuron

Slow axonal- one way mechanism from the cell body only down the axon, its used axonplasm, moves from 1-5 ml per day

Occurs- in growth and development and the repair nerve damage

Fast axonal- daily maintenance of a neuron 2 way mechanism from cell body to axon, 200-400 ml per day

Differentiate between the autonomic vs. somatic nervous systems

ANS- deals with subconscious sensation and the control of smooth muscle, cardiac, gland secretion, involuntary

somatic- consciousness sensation and involved with skeletal muscle, voluntary in control

Know term meaning a collection of cell bodies found outside the CNS 

Ganglia

Know inferior (caudal) structures associated with the spinal cord

1. conus medullaris (tapered into the spinal cord L1, L2)

2. Film terminale (little thread of fiber that attach to the Coxyx)

3. Courage (horse tail, nerve roots coming off of spinal cord)

Order of the meningeal layers (superficial to deep, vice-versa)

Superficial- dura

Middle - arachnoid

Deep- piaarachnoid

Know area of spinal cord that contains cell bodies of the somatic and autonomic motor neurons

Somatic- cell bodies originate anterior gray horn

Automatic- lateral gray horn

What is contained in the posterior (dorsal) root ganglion?

Contains cell bodies of unipolar sensory neurons

What are the 5 components of a reflex arc?

1. Sensory receptor

2. Sensory neuron

3. Integrative center

4. Motor Neuron

5. Effector

What is the basic function of a sensory receptor?

Sensory receptor that converts a stimulus into a nerve impulse

Know the difference between the stretch, tendon, and flexor, crossed extensor reflexes.

They are all spinal somatic reflexes, they all have spinal cords and spinal nerves

Stretch- mono synaptic, ipsilateral, segmental

What it does- involved in muscle spindle, prevent overstretching of muscle

Tendon- poly synaptic, ipsilateral, segmental

Involves- a receptor called tendon organ, which prevents excessive tension.

Flexor- poly synaptic, ipsilateral, intersegmental reflex

Involves- pain receptor, nociceptor, (effect is that it withdrawal the limb from the pain source)

Cross- poly synaptic, contral lateral, intersegmental

Effect- contact extensor muscle on the opposite side of the body for stabilization

How many pairs of spinal nerves are found in the human body?

31

8-cervical

12- thoracic

5- lumbar

5- sacral

1-coccyx

Know the difference between the endoneurium, perineurium and the epineurium

Endoneurium- surrounds each axon in a nerve

Perineurium- wraps on the fascials of axon

Epineurium- surrounds the entire nerve

Know the areas supplied by each ramus of the spinal nerve

Ramus- a branch of spinal nerve

Posterior ramus- supplies deep muscle and skin on back of the body

Anterior ramus- largest, supplies superficial back muscles (front and side of torso) upper limb and lower limb

Mengingial ramus- menginngs and blood vessels

Rami- connects to automatic nervous system sympathetic division

Know the areas supplied by each plexus

1. Cervical plexus- supplies back of the head,neck, top of shoulder, diaphragm

2. Brachial plexus- top upper limb (shoulder to finger tips)

3. Lumbar plexus- anterior lateral supplies part of lower limb and goes to genitalia (thigh ankle foot)

4. Sacral plexus- back of the thigh, calf, ankle, bottom of foot, booty, perineum

Define:  dermatome

Is a constant specific area of skin connected to a specific spinal nerve

Know the 4 principle parts of the brain (with subdivisions).

Brain stem- principle

Subdivision- medulla, pons, midbrain

cerebellum- 2nd largest area of the brain located posterior to brain stem

diencephalon

Subdivision- thalamus, hypothalamus

Cerebrum-7/8 of brain

Subdivision- Coro plexus protects caf

Where is cerebrospinal fluid (CSF) produced, and in what space does it circulate?

CSF secreted by Coro plexus, which is located in the 4 ventricles inside the brain. It circulates around the arachnoid space

What is the principle source of energy for the brain cells?

Glucose

Where are the cardiac and vasomotor centers located?

In the medulla area of the brain

Know the cranial nerves (names, Roman numerals, and origins)

1. 3&4- originate in mid brain

   5,6,7, ½ 8= ponds

   ½ 8-12=- medulla

   Function

   3,4,6= eyeball movement

What are the functions of the hypothalamus?

Small area inferior to the thalamus,

1. involved with coordination and control of ans,

2. Thirst center

3. Hunger/ full center

4. Temperature

5. Link between nervous and endocrine says

6. Secreted Adh and oxitosin

7. Sleeping and waking

8. Psychosomatic disorders

9. Feelings of emotions

What are the deep & shallow grooves in the surface of the brain called?

Deep- fissure

Shallow- sulcus

Where are visual sensations identified?

Occipital lobe

Where is the primary motor area of the brain located?

Pre central gyrus

Left side control right muscle

Right side control the left muscle

What is the cerebellum's function?

Receive sensory information from all over the body

Quickly coordinate skeletal muscle like balance, posture, equilibrium

Know cranial nerve function - see handout

Function

3,4,6= eyeball movement

1= smell

2= sense of Vision

8= hearing & equilibrium

Know where the different functional sensory and motor areas are located on the cerebral cortex.

Primary somatial sensory area

Poster centeral gyrus of peritial lobe- primary sensation area

Occipital lobe- vision

Temporal- hearing and old factions

Anterior lateral- gustatory so sense of taste

Wernickes area- when visual a picture from story

common integrative area- total sensory experience

Motor

Primary motor area —>Pre central gyrus of frontal lobe- control muscle on opposite of the body

Bronca- speech production

Pre motor area- complex learned motor skilled

Frontal eye field

Know the different neuropeptides

Enkephalin- reduce pain, 200 more powerful than morphine

Endorphins- modify pain

Dynorphins- modify pain

substance p- transmits pain signals

What plexus supplies the diaphragm?

Cervical plexus

Which part of the brain links the nervous & endocrine system?

Hypothalamus

Understand how the destruction of different parts of the cerebral cortex would result in specific losses of sensory perception or motor control

Example

1. Occipital

1. Is there’s a problem with the right pre gyrus it’s going to effect motor on the left side

2. Or if there’s something wrong with the bronchus it’s going to effect the speech

Where are the apneustic and pneumotaxic centers located?

pontine respiratory center

Know what a positive Babinski's reflex (sign) is & what is it indicative of in an adult?

positive if the toes stick up, in adult (over 18 months) they would have a cns lesion like something is wrong in the brain/spinal cord

Know the different neuropeptides

Trigeminal Neuralgia

Pain occurring in area of the face

​Shingles

Viral infection that causes a rash

Paresthesia

Pins and needles sensation temporary in arms,hands,feet

Cerebrovascular accident

Stroke

Analgesia

Relieve pain ,Reduced pain,

​Sciatica

Pressure on the sciatic nerve

Agnosia

Loss of the ability to identify people or objects

Multiple Sclerosis

Disease that demylinating axons in the cns

​Nerve Block

Procedure that involves injecting a thing or medication to target a group of nerves to block pain signals

LATERAL GRAY HORN    

Area of spinal cord that contains cell bodies for automatic motor neurons

POSTERIOR GRAY HORN

Area of spinal cord that receives unipolar sensory neuron

ANTERIOR GRAY HORN

Spinal cord division that controls motor movement