Nervous System

Question 1

How is information gathered in the body?

Answer 1

Both inside and outside the body, this sensory input is sent to the CNS via the peripheral nerves

Question 2

Sensory fiberes are also called

Answer 2

Afferent fibers

Question 3

How does sensory information travel?

Answer 3

From the PNS to the CNS

Question 4

Sensory information types

Answer 4

Pin, pressure, temperature and chemical levels

Question 5

Central nervous system consists of

Answer 5

Brain and spinal cord

Question 6

CNS Function

Answer 6

Processes and integrates sensory information can be stored to be dealt with or acted upon immediately with one or more motor responses

Question 7

Peripheral nervous system motor division

Answer 7

Carries impulses away from the CNS usually to effector organs (muscle, glands, heart)

Question 8

Motor fibers are also called

Answer 8

Efferent fibers

Question 9

PNS Divisions

Answer 9

Somatic nervous system
Autonomic nervous system

Question 10

Somatic nervous system

Answer 10

Voluntary control and effector organs respond to instructions from the CNS for skeletal muscle movement

Ex open window if hot

Question 11

Autonomic nervous system

Answer 11

Involuntary responses in response to CNS

EX Vasodialation

Question 12

PNS further divisions

Answer 12

Parasympathetic (Rest and digest) and sympathetic nervous system (Fight or flight)

Question 13

Neurons

Answer 13

Functional unit of the nervous system, has a nucleus and mitochondria

Question 14

Neuron characteristics

Answer 14

Ability to initiate other nerve responses
Ability to conduct an impulse

Question 15

Parts of the neuron

Answer 15

Axon, dendrite and cell body

Question 16

Neuron parts function

Answer 16

Transmit nerve impulses, traveling from the dendrite, the receiving area to the cell body down the length of the axon

Question 17

Dendrites

Answer 17

Short branching processes that recieve information and conduct toward the cell body , branching provides a large surface area for one neuron to the next

Question 18

Cell Body

Answer 18

Located in the CNS and form the grey matter, clusters of cell bodies are grouped in the CNS, it is called nuclei Cell bodies in the PNS are called ganglia

Question 19

Axon

Answer 19

Info away from the cell body, can form an axon collateral, delivers the impulse to another neuron or gland or a muscle, branch at its terminal into many axon terminals

Question 20

What is a myelin sheath?

Answer 20

Fatty material with the purpose of to protect the neuron and provide electrical insulatio, speeding up impulse tranlation.

Question 21

What are the myelin sheaths in the PNS called

Answer 21

Schwann Cells

Question 22

Outermost part of Schwann is called

Answer 22

Plasma membrane (myelinated and unmyelinated covering) which forms together the neurolemma for protection and regrowth

Question 23

What are the gaps between the Schwann cells called

Answer 23

Nodes of Ranvier Axon collaterals can occur at the node

Question 24

Unmyelinated axons transmit signals

Answer 24

Slower

Question 25

Sensory or Afferent Nerves

Answer 25

Dendrites of sensory neurons are sensory receptors and when stimulated they travel toward the spinal cord and brain

Question 26

Types of sensory receptors

Answer 26

Special senses Somatic sensory receptors- skin temp and touch Autonomic nervous system baroreceptors throughout the body, monitoring BP, chemoreceptors, blood pH and visceral pain receptors Proprioceptors monitoring muscle movement stretch and pain

Question 27

Motor Efferent Nerves

Answer 27

Info from the CNS to the PNS is delivered via motor nerves voluntary somatic nerve-muscle contraction Autonomic nercous system-smooth muscle contraction or gland release

Question 28

Action potential

Answer 28

Conducted impulses to communicate sending messages from the internal and external environment to the CNS and from the CNS to muscle and glands Occur due to movement of ions into and out of the neuron and electrical charge associated with the movement

Question 29

2 ions in action potentials

Answer 29

Sodium outside cell Potassium inside cell

Question 30

Nerve impulses process when activated (Simple Propagation)

Answer 30

No impulse, the nerve is at rest stimulated the membrane changes permeability and sodium flows into the cell called depolarization Changes electrical charge from positive to negative charge outside the cell as the impulse travels axon distance Potassium ions flow out of the cell returning the electrical charge to positive inside and negative outside this is called repolarization The sodium-potassium pump is activated to return sodium outside the cell for potassium

Question 31

Saltatory conduction

Answer 31

Occurs in myelinated neurons as the electrical charge associated with the nerve impulse jumps between nodes of Ranvier ( Faster than propagation)

Question 32

Refractory period

Answer 32

When action potential is activated, it cannot accept another impulse or generate another action potentialno matter how intense the impulse is

Question 33

What are glial cells and their types

Answer 33

Glial cells -support and protect neurons Insulation Support and protection Nutrient supply Waste removal Brain circulation Neurotransmitter regulation Astrocytes- CNS-from blood-brain barrier regulate neurotransmitters, ion balance and repair brain and spine following injury, blood flow to the brain Oglidendrocytes CNS-produce myelin Microglia CNS immune cells to CNS remove debris through phagocytosis Ependymal CNS produce cerebral spinal fluid

Question 34

Spinal cord structure

Answer 34

Begins at the foramen magnum, the largest hole at the base of the skull, which connects the brain to the rest of the body

Question 35

Spinal reflex arc

Answer 35

Receives signals from the body and relays immediate responses via motor neurons to take action without brain intervention. The brain modulates this process Survival mechanism to the environment

Question 36

Spine size and look

Answer 36

Spine is 1inch in diameter, grey matter is in the center, divided into posterior (Dorsal or back), anterior (ventral or front), and lateral horns The spine runs from the base of the skull to the tailbone

Question 37

What neurons enter the posterior horn? What does this look like?

Answer 37

Afferent, entry area is swollen due to cell bodies, the swellings are called ganglia, these nerves then connect with motor neurons, which exit on the anterior side

Question 38

Spinal cord anatomy

Answer 38

The spine runs from the base of the skull to the tailbone, the atlas holds the skull up and the axis allows it to rotate

Question 39

Spinal axis 4 Sections

Answer 39

8 spinal nerves exit at the cervical or neck section 12 spinal nerves exit at the thoracic or chest section 5 spinal nerves exit at the lumbar or back section 5 spinal nerves exit the sacrum, at which the vertebrae is fused together

Question 40

Spinal curve description and coverings

Answer 40

Curved in an anterior-posterior (front and back and alternate between convex and concave, spine acts as spring and is similarly covered from the skull and brain Spinal column is like the skull and the meninges are like that of the brain

Question 41

What are the three meninges?

Answer 41

Dura mater Pita mater Arachaniod

Question 42

Spinal spaces and CSF

Answer 42

Epidural Subdural Subarachnoid CSF in these spaces are continuous with the brain

Question 43

Reflex Arc pathway

Answer 43

The skin (peripheral receptor recieves intense heat from a hot stove Impulse travels up the nerve through the neuron body in the posterior side of the spine and into the dendrite of the posterior horn grey matter Associateion neuron in the posterior side grey matter alerts the brain and lower motor neuron on the anterior side Impulse exits the cord on the anteror and triggers muscle to remove hand

Question 44

Reflex arc types

Answer 44

Knee reflex test Monosynaptic arc-no combining signal neurons Stretch in the femoral muscles to the cord and back down the femoral muscles Ex knee jerk Polysynaptic- Antagonistic muscle of the hamstrings to not move so the femoral muscle can move the leg

Question 45

Spinal Nerves

Answer 45

Exit the body in spinal segments to connect with the body and brain Posterior and anterior mix to form a mixed nerve Surrounded by protective muscle and bone compression ofd cord and nerves can happen with slight shifts Mixed nerves are covered by epineurium (outer)and and group into bundles called fascicles, covered by perineurium (middle)Endoneurium covers each anxon