Unit 3 GAP CVTC

What is neurology?

Study of nervous system

Sensory function of nervous system

Detects external and internal stimuli

Integration function in nervous system

Analyzes sensory info and makes decision on how to respond

What is the motor function of the nervous system

Respond to info by muscle contraction or gland secretion

Neurons

Produce nerve impulses called action potentials

Dendrites

Recives signals and conduct them towards cell body

Axon

Conducts action potentials away from cell body towards other neurons,

Excitability

Responsiveness to a stimulus

Conductivity

Ability to spread electrical signal

Secretion

Release of neurotransmitter in response to conductive activity

Extremelogevity

Cells can live through a persons life

Amitotic

No mitotic activity

Afferent neurons or sensory neurons

Carry sensory information to the central nervous system

Motor neurons or effectrent neurons

Carries infomation from central nervous system to muscles or glands

Interneurons or association neurons

Connect sensory neurons to motor

Neuroglia

Make up half of the volume of CNS and they support, nourish and protect nerve cells

Astrocytes

Support neurons, make up the blood brain barrier, maintain chemical balance, and influence formation of neural synapses for learning and memory

Oligodenderocytes

Form myelin sheaths

Mircroglia

Engulf dead cells

Phagocytize

Engulf and digest certain particles

Ependymal cells

Form cerebrospinal fluid (CSF)

Schwann cells

Form myelin sheaths

Satellitle cells

Support neurons and regulate exchanges

What are myelin sheaths composed of

Lipids and proteins

What are myelin sheaths produced by

Schwann cells in pns and oligodendrocytes in cns

What do myelin sheaths do

Insulates axon and increases the speed of a nerve impulses

Nodes of ranvier

Gaps in myelin sheaths

Nerve

Bundle of axon, dendrites, or both in the pns

Cranial nerve

Connect brain to periphery

Spinal nerves

Connect spinal cord to periphery

Whats the inner most layer of connective tissues that surround the nerves

Endonurium

Whats the middle layer of connective tissues that surround the nerves

Perinurium

Whats the outer most layer of connective tissues that surround the nerves

Epinerium

Where are most cell bodies found

CNS

Tracts

A bundle of nerves or axon in CNS

Ascending tracts

Go up the spinal cord and carry sensory information

Descending tract

Go down the spinal cord and carry motor infomation

What type of matter is myelinated

White matter

What type of matter is unmyelinated

Grey matter

What does CNS stand for

Central nervous system

What does PNS stand for

Peripheral nervous system

Components of the CNS

Brain and spinal cords

Function of the CNS

Integration

Components of the PNS

Nerve, ganglia, sensory receptors

Sensory function of pns

Collect impulses using senses and carries them to the CNS

Motor function of PNS

Carries a response away from CNS to muscles or glands

Synapse

Place where 2 neurons meet, but never connect

Prosynapic neuron

Neuron sending the impulse

Postsynopic neuron

Neuron receiving the impulse

Neurotransmitter

Chemical messenger that the brain and nervous system use to send signals from one nerve cell to another or to muscles and glands

Acetylcholine (Neurotransmitter)

Stimulates skeletal muscle contractions

Dopamine (Neurotransmitter)

Pleasure, movement, motivation

Endorphins (neurotransmitters)

Released during exercise and sex

Serotonin (Neruotransmitter)

Contributes to wellness

Multiple sclerosis

Autoimmune disease that progressively destroys myelin sheaths in the CNS

Epilepsy

Periodic episodes of seizures caused by abnormal electrical firing of neurons in the brain

Meninges

3 layer of tough connective tissue coverings

Mengitis

Inflammation of meninges due to infection

What is cerebrospinal fluid

Colorless fluid that spinal cord and helps with shock absorption

Cervical enlargement

Nerves for arms enter and exit here

Lumbar enlagement

Nerve for the legs enter and exit here

What is gray matter surrounded by

White matter

Central canal

Hole in center, contains CSF

How many pairs of spinal nerve

31

Root (Spinal nerve organization)

Bundle of nerves

Dorsal or posterior root (Spinal nerve)

Carriers sensory information to spinal cord

Dorsal root ganglion (Spinal nerve)

Contains cell bodies of sensory neurons

Ventral or anterior roots (Spinal nerves)

Carriers motor information away from spinal cord

Spinal plexuses

Network or group of nerves

Neck plexus

Located in neck

Brachial plexus

Near armpit

Lumbar plexus

Lower back

Sacral plexus

Sacrum

Sciatica

Caused by injury, pain radiates from butt down the back of leg

Spinal cord function

Carries messages to and from the brain

Posterior column tracts

Carries touch and creates the ability to sense own position, movement, and force without needed to look at limbs

Spinothalamic tract

Carries pain and temperature

Pyramidal/direct tracts

Carry nerve impulses for voluntary movements

Extrapyramidal/indirect tracts

Carry nerve impulses for unconscious/involuntary movement

Reflex

Automatic involuntary physical reaction to a stimuli

Receptors

Receives stimulus and creates nerve impulses

Sensory neurons

Carries nerve impulses to spinal cord

Integration center

Gray matter of spinal cord that decides what to do

Motor neuron

Carriers response to effector

Effector

Muscle/gland that responds/effects

Contusion of spinal cord

Spinal cord is bruised

Complete transaction of spinal cord

Cord is severed

Paraplegia

Damage to the thoracic region can cause paralysis from the waist down

Quadiplegia

Injury to the cervical region can cause paralysis from neck down

What 3 things protect the brain

Cranium, 3 layers of meninges, and csf

How many lateral ventricles

2

Choroid plexus

Found in walls of the ventricles and they produces CSF

Hydrocephalus

Pressure builds up in ventricles because CSF doesn’t properly drain

Medulla oblongata (Part of brain stem)

Continuous with spinal cord, contains all ascending and descending tracts

Pyramids

2 bulges where motor tract cross through

Decussation

Motor tracts cross over, this is why left side of brain controls rights side and vise versa

Functions of medulla oblongata

Control center for vomiting, coughing, sneezing, swallowing

Pons

Bridge between medulla oblongata and midbrain, controls breathing and regulates information

Midbrain

Contains some tracts to relay information

Superior colliculi

Visual reflex center