The Nervous System

Question 1

What are the 3 types of neurons? What do they do?

Answer 1

Sensory, carry info from sensory receptors on skin to CNS (Central Nervous System).
Interneurons, integrate, and transmit from sensory neuron to motor neuron.
Motor Neuron, carry info from CNS to glands and muscles.

Question 2

What are the 2 Nervous systems?

Answer 2

Central and Peripheral

Question 3

What composes the CNS?

Answer 3

Brain and Spinal chord

Question 4

Is the PNS sensory or motor?

Answer 4

Sensory

Question 5

Is the CNS sensory or motor?

Answer 5

Motor

Question 6

What compiles the Sensory somatic Nerves?

Answer 6

Motor and Sensory Neurons

Question 7

Autonomic Nervous system is comprised of what?

Answer 7

Sympathetic and Parasympathetic nerves

Question 8

What are the parts of a Neuron?

Answer 8

Dendrites
Cell body
Myelin Sheath
Nodes of Ranvier
Axon Endings
Schwann Cells
Axon

Question 9

What is the Function of the Dendrites?

Answer 9

It contains receptors to receive and transmit information into the neuron.

Question 10

What is the Function of the Cell Body?

Answer 10

Contains the Nucleus.

Question 11

What is the Function of the Myelin Sheath?

What colour matter is it?

Answer 11

Fatty Proteins are used for insulation and speeds up the transmission. White Matter.

Question 12

What is the Function of the Nodes of Ranvier?

Answer 12

Gap between Myelin Sheath. Where SALTATORY CONDUCTION occurs.

Question 13

What is the Function of the Axon Endings?

Answer 13

knobs contain synaptic vesicles. They transmit info from the axons to the dendrites of the next neuron.

Question 14

What is the Function of the Schwann Cells?

Answer 14

Glial cells that form the myelin sheath. Wrap around the axon tail to protect it and to increase the neuro-impulse speed with SALTATORY CONDUCTION.

Question 15

What is the Function of the Axon?

Answer 15

Extension of cell body. Carries the impulses.

Question 16

What are the 3 types of Neurons?

Answer 16

Sensory Neurons
Interneurons
Motor Neurons

Question 17

What do Sensory Neurons do?

Answer 17

They carry info mainly from the sensory receptors in your skin to the CNS

Question 18

What do Interneurons do?

What Colour Matter is it?

Answer 18

Integrate and Interpret info, and transmits the info from Sensory to Motor Neurons.
Grey Matter.

Question 19

What do Motor Neurons Do?

Answer 19

Carry information from CNS to effectors which are mainly bones and Muscles.

Question 20

What are the various Reflex Arcs?

Does not need to be in order!!

Answer 20

1. Sensory Receptors
2. Sensory Neurons
3. Interneurons
4. Motor Neurons
5. Effector

Question 21

What is a threshold level and what is it ordinarily?

Answer 21

it is the level of stimulus required to produce a response or to fire.
Normally -55mV

Question 22

What happens during Depolarization?

This one is tricky. You don’t need to know ALL of it (immediately).

Answer 22

Polarity changes to +40mV.
Increases Na+ permeability down the Axon.
Myelin speeds up depolarization because most Na+ channels are found at the nodes of Ranvier.
The greater Na+ ions require Na+ to move into the cell to pass the signals. This is called SALTATORY CONDUCTION!

Question 23

What is the “All or None Response”?

Answer 23

The Neuron either reaches the threshold of -55mV and fires or it doesn’t. This is called Summation.

Question 24

What do ECF and ICF stand for and which is in what for the sodium potassium channels?

Answer 24

ICF- Intracellular Fluid (Mainly Potassium (K+))

ECF- Extracellular Fluid (Mainly Sodium (Na+2))

Question 25

What do the Reflex Arcs do in relaying info?

Answer 25

1. Sensory Receptors- recognizes environmental changes.
2. Sensory Neurons- relays info to grey matter (interneuron).
3. Interneurons- transmits to white matter (motor neuron)
4. Motor Neurons- carries impulse to proper organ (muscles mainly)
5. Effector- the response