Quiz 7 study

Question 1

What are the 3 types of neurons

Answer 1

Sensory, motor and interneurons

Question 2

What are the Subcomponents of the Axon?

Answer 2

The axon hillock - the area where the soma turns into the axon
the Collateral branch - often protrudes off at a right angle

Question 3

What are the components of the collateral branch

Answer 3

Roleodendra - each of which contains a terminal button which is half of the synapse

Question 4

What are the components of the Dentrite?

Answer 4

Branches (up to 20) subdivide into Dendrite spines (thousands per branch) which connect to axon roleodendra to form the synapse

Question 5

Two main components of the soma

Answer 5

Nucleus and nucleolus

Question 6

What are the sensory neurons distinguishing features, and list 2 examples

Answer 6

Small and simple, entirely afferent.

1. Bipolar neuron - simple one axon, one dendrite neuron in the eye
2. somatosensory neuron - sends afferent info to the spinal cord a long distance, the soma lies off the side as the axon and dendrites are integrated

Question 7

What is the function of interneurons, and list the 3 examples

Answer 7

relay information from the afferent sensory neurons to the efferent motor neurons.

1. Pyramidal - pyramid-shaped cell body with 2 dendrite pairs
2. Stellate - a very small star-shaped cell with a lot of dendrites
3. Purkinje - Fan-shaped dendrites, sends info from the cerebellum to the brain and spinal cord.

Question 8

Function and features of the Motor Neurons

Answer 8

send efferent signals
larger, with extensive dendrites and long axons connecting to muscles
all reside in the lower brain stem and spinal cord

Question 9

What are the 5 Glial cells and their MAIN function?

Answer 9

1. Ependymal - secrete CSF
2. Astrocyte - the Blood-brain barrier
3. Microglia - immune system offset, monitors brain health
4. Oligodendroglia - Myelinates axons
5. Schwann cells - Myelinates axons

Question 10

Specific functions of the Ependymal

Answer 10

• Exist on the walls of the ventricles and secrete CSF which serves to:
  1. Shock absorb
  2. Carry away waste
  3. Temperature maintenance
  4. Provides nutrients to the brain. areas adjacent to the vents

Question 11

Specific functions of the Astrocyte

Answer 11

Provides structural support to the CNS by attaching its extensions to blood vessels using them to stabilize

• contributes to the blood brain barrier by binding to tight junctions on the blood vessels, further sealing the barrier
• enhance brain activity by signalling the blood vessels to increase their blood flow to increase glucose and oxygen coming into the brain
• Also scar to repair trauma

Question 12

Specific functions of microglia

Answer 12

originate in the immune system and makeup 20% of glial cells
Monitor and maintain brain health in 2 ways-
1. Secretes growth factors when damaged to repair and replace lost neurons
2. Phagocytosis (eats) foreign tissue and dead brain cells
May play a role in Alzheimer’s

Question 13

Specific function of Oligodendroglia

Answer 13

Myelinate axons in the CNS by sending out large branches which enclose and seperate adjacent neurons
Contribute to neuron nutrition and function by absorbing chemicals they produce and producing chemicals for them to use

Question 14

Specific function of the Schwann cells

Answer 14

Myelinate axons in the PNS by wrapping around them several times
Also, contribute to nerve regeneration after damage by acting as a trail of breadcrumbs for the new axon to follow to the required synapse
Contribute to neuron nutrition and function by absorbing chemicals they produce and producing chemicals for them to use

Question 15

What are the 3 types of brain tumours and their characteristics

Answer 15

Gliomas: Derived from glial cells, grow slowly and typically begning
Meningiomas: Attach to the meninges,
Metastic tumours: