L-16

Question 1

What are the two divisions of the nervous system?

Answer 1

CNS + PNS

Question 2

What is the CNS composed of?

Answer 2

The brain + spinal chord

Question 3

What is the PNS composed of?

Answer 3

The peripheral nerves and ganglia

Question 4

What are the two broad cell types of the nervous system?

Answer 4

Neurons and glia

Question 5

What are the 4 main structural components of the Neuron?

Answer 5

• Dendrites
• Cell body
• Axon
• Axon Terminals

Question 6

What do dendrites do?

Answer 6

Recieves information and sends to cell body

Question 7

What is the function of the cell body?

Answer 7

Contains the nucleus + organelles and sums input information

Question 8

What is the function of the axon?

Answer 8

Carries action potentials

Question 9

What is the function of the Axon terminals?

Answer 9

Release the neurotransmitter in a synapse to communicate with other neurons

Question 10

What are the 4 Morphological types of neurons?

Answer 10

• Unipolar
• Bipolar
• Multipolar
• Anaxonic

Question 11

What makes a neuron unipolar?

Answer 11

Cell body lies to the side of main axon ( most PNS sensory neurons are unipolar)

Question 12

What makes a neuron bipolar?

Answer 12

Two distinct processes branching off cell body ( one dendritic and one axonic)

Question 13

What makes a neuron Multipolar?

Answer 13

Multiple dendrites branching off cell body with a singular axon (most common type found in CNS)

Question 14

What makes a neuron anaxonic?

Answer 14

Poorly understood, located within brain and sensory organs, don’t have a clear axon

Question 15

What is the input zone composed of and what does it do?

Answer 15

• dendrites +cell body

- receives chemical signals

Question 16

What is the summation zone composed of and what is its function?

Answer 16

• Axon Hillock

- summation of inputs

Question 17

What is the conduction zone composed of and what is its function?

Answer 17

• Axon

- Carrie’s electrical impulses

Question 18

What is the output zone composed of and what is its purpose?

Answer 18

• Axon terminals

- release of neurotransmitter

Question 19

How many basic types of Glial cells are there? Where are they found in the nervous system?

Answer 19

• 5
• 4 in CNS
• 1 in PNS

Question 20

What are the 4 types of CNS Glia called?

Answer 20

• Astrocytes
• Microglia
• Ependymal cells
• Oligodendrocytes

Question 21

What is the function of Astrocytes? (4)

Answer 21

• Supply nutrients to neurons
• ensheath blood capillaries
• injury response
• controls chemical environment around neurons

Question 22

What is the functions of Microglia? (3)

Answer 22

• Act as immune cells of CNS
• engulf microorganisms and debris
• respond to injured neurons and protects them from pathogens

Question 23

What are the functions of Ependymal cells? (2)

Answer 23

• Line fluid filled spaces of brain and spinal chord

- cilia aid in circulation of CSF

Question 24

What is the function of Oligodendrocytes?

Answer 24

• Form myelin sheath around CNS neurons

Question 25

What is the name of PNS Glia?

Answer 25

Schwann Cells

Question 26

What is the function of Schwann Cells?

Answer 26

- form myelin sheath for PNS axons

Question 27

What is a group of cell bodies in the CNS called?

Answer 27

Nucleus

Question 28

What is a group of axons in the CNS called?

Answer 28

A Tract

Question 29

What is a group of cell bodies in the cerebral cortex or spinal chord called?

Answer 29

Grey matter

Question 30

What is a bundle of axons in the cerebral cortex or the spinal chord called?

Answer 30

White matter

Question 31

What is a group of cell bodies in the PNS called?

Answer 31

A ganglion

Question 32

What is a bundle of axons in the PNS called?

Answer 32

A nerve

Question 33

What is a myelin sheath?

Answer 33

Lipid ( fat) wrapped around an axon that acts as an insulator and increases conduction velocity.

Question 34

What are gaps in the myelin sheath / between Schwann cells called?

Answer 34

Nodes of Ranvier

Question 35

What is a synapse?

Answer 35

The junction between neurons that allows for communication between them using neurotransmitters

Question 36

How does communication occur at a synapse ( broadly)

Answer 36

An action potential stimulates a chemical release from the axon terminals of the pre-synaptic neuron that can then bind to receptors in the dendrites of the postsynaptic neuron.

Question 37

Which direction is afferent information going?

Answer 37

Towards the brain

Question 38

Which direction is efferent information going?

Answer 38

Away from the brain