Nervous System

Question 1

The main function of the nervous system is

Answer 1

to control and coordinate all body functions
It responds to internal and external stimuli

Internal – hunger, thirst, fear…
External – sight, sound, pressure…

Question 2

Parts of nervous system

Answer 2

• brain
• spinal cord
• and all the nerves

Question 3

the brain, 3 main parts

Answer 3

• Cerebrum
• Cerebellum

-Brain stem:
The pons
The medulla oblongata

Question 4

Cerebrum

Answer 4

Is the largest part

Is the centre for thought and intelligence, movement and memory, language and emotion

Question 5

Cerebellum

Answer 5

Co-ordinates movements and balance

Also called “little brain” or hind brain

Question 6

Brain stem

Answer 6

Connects other parts of the brain to the spinal cord

Made up of pons and medulla oblongata

Question 7

what are the brain subsystems

Answer 7

Central nervous system

Peripheral nervous system

Autonomic nervous system

Question 8

Central nervous system

Answer 8

• Includes the brain and spinal cord
• where information is processed
• Receives from and sends information to the peripheral nervous system

Question 9

Peripheral nervous system

how many pairs of cranial nerves

How many spinal nerves

Answer 9

Consists of all the nerves going to (sensory) and from (motor) the spinal cord

There are 12 pairs of cranial nerves

There are 31 pairs of spinal nerves

Question 10

Autonomic nervous system

Answer 10

Responsible for involuntary functions
HR, digestion, respiration rate, urination, sexual arousal etc.
Divided into sympathetic and parasympathetic

Question 11

sympathetic and parasympathetic in ANS

Answer 11

SYMPATHETIC
“ Fight or flight ”
Speeds things up in times of stress/crisis
Ex. respiration, HR, BP, shunts blood away from core of body to periphery
Adrenal glands secrete adrenaline (epinephrine)

PARASYMPATHETIC- vagus nerve has control
“Rest and Digest”
Slows things down
Balances the sympathetic by counteracting its effects
Ex. **Decrease in HR, BP, shunts blood to the core and away from limbs
Acetylcholine

Question 12

Ardrenal Glands

Answer 12

• Sit on top of each kidney
• Produce hormones that help to control the nervous system

-Epinephrine – Adrenalin
Secreted by adrenal medulla

• Testosterone
• Precursor to estrogen

Question 13

how is homeostasis achieved in NS

examples

Answer 13

This is achieved through the opposing functions of the sympathetic and parasympathetic nervous systems

such as: 
Fluid balance	
Electrolyte balance	
Body temperature
Blood pressure
Heart rate

Question 14

what are nerves made of

can they repair

Answer 14

Made of nerve cells called neurons

Can repair but only at a very slow rate
Injuries to nerves can become permanent

Question 15

Parts of a neuron

Answer 15

Dendrites: short fibers that extend from the body of the cell; receive the messages from the adjacent nerves

Synapse: junction from one neuron to the next neuron, or to the muscle, or organ, **sends messages

Myelin Sheath:
Fatty covering of the axon allowing for nerve impulse conduction

Axon: long process that extends from the nerve cell; transmits the message to the next neuron

Question 16

Types of neurons

Answer 16

Motor- Carry messages out from the brain to muscles

Interneuron/Mixed - Nerves that perform both sensory and motor function

Sensory- Carry messages to the brain and spinal cord bringing sensory information such as pressure, temperature, pain

Question 17

How nerves fires

Answer 17

A nerve impulse is also known as an Action Potential

Fire on an all or nothing principle
Actional potentials allow for cell-to-cell communication

Question 18

How does Action Potential work

Answer 18

A resting nerve cell is negatively charged
When the nerve begins to “fire”, channels in the membrane of the nerve open and allow Na+ and K+ to enter the cell

Inside of the cell becomes positively charged
The positive charge travels along the nerve axon to the axon terminal (end of the nerve cell)

When the charge reaches the end of the nerve cell, chemicals called neurotransmitters are released

These chemicals cross the gap between the previous nerve cell (Synaptic cleft) and the next nerve cell to begin the process all over again and continue the nerve signal

Question 19

All-Or-None principle

Answer 19

A nerve will fire regardless of the strength of stimulus, as long as the stimulus exceeds the threshold potential of the cell
It either fires or it doesn’t

Question 20

SALTATORY CONDUCTION

Answer 20

When the action potential travels down a nerve, it can “jump” along the axon on the myelin sheath
This spends up the transmission of the nerve impulse

Question 21

Nervous System Disorders

Parkinson’s Disease

Answer 21

Progressive degeneration of motor function (motor disfunction)
Signs/Symptoms
Shuffling gait
Pill rolling tremor

Question 22

Nervous System Disorders

Multiple Sclerosis

Answer 22

• disease of nerves in the brain and spinal cord
• autoimmune

Signs/Symptoms

• Random neurological symptoms
• Visual, motor, sensory

Symptoms often increase with heat

Question 23

Nervous System Disorders

Alzheimer’s Disease

Answer 23

no cure
Most common cause of dementia

Signs/Symptoms

• -Memory loss
• -Confusion
• Mood Changes
• Difficulty speaking, swallowing, walking

Question 24

Nervous System Disorders

Amyotrophic Lateral Sclerosis (ALS)

Answer 24

Motor neuron disease
Unknown cause
Progressive and fatal

Signs/Symptoms

• Stiff muscles, twitching, and weakness
• Eventually inability to _speak, swallow, or breath

Question 25

Functions of Cranial Nerves

Answer 25

``` CN I – Smell CN II – Sight CN III – Eye Movements CN IV – Eye Movements **CN V – Facial Sensation and chewing CN VI – Eye Movements **CN VII – Facial Expression CN VIII – Hearing and Balance CN IX – Oral Sensation Taste and Salivation **CN X – Parasympathetic Control **CN XI – Shoulder Elevation and Head Rotation CN XII – Tongue Movement ```

Question 26

Names of Cranial Nerves 1-12 ``` O O O T T A F V G V A H ```

Answer 26

``` CN I – Olfactory CN II – Optic CN III – Oculomotor CN IV – Trochlear CN V – Trigeminal CN VI – Abducens CN VII – Facial CN VIII – Vestibulocochlear CN IX – Glossopharyngeal CN X – Vagus CN XI – Accessory CN XII – Hypoglossal ```

Question 27

The Trigeminal Nerve has three main branches what are the sub branches

Answer 27

``` V1: Ophthalmic -supraorbital -supratrochlear -nasal V2: Maxillary -zygomatic n -infraorbital n V3: Mandibular -auriculotemporal n -lingual n ```

Question 28

The Facial Nerve has 6 Branches

Answer 28

``` Temporal Branch Zygomatic Branch Buccal Branch Mandibular Branch Cervical Branch Occipital Branch ```

Question 29

The Vagus Nerve - where is it located - does it affect CNS, PNS, or ANS? - what happens if its triggered

Answer 29

- travels down the abdominal cavity - ANS - drops blood pressure, most common cause of fainting

Question 30

Accessory nerve branches

Answer 30

- greater auricular n -greater occipital n | - cervical Cutaneous n -smaller occipital n