Neurological Cytology

Question 1

What are the function of dendrites

Answer 1

Receives signals from other neutrons

Question 2

What is the function of the axon

Answer 2

Transmit electrical impulses to pre synaptic terminals

Question 3

What is the function of Oligodendrocytes (Schwann cells in the PCN)

Answer 3

Form the myelinated sheath
Give nutrients to neuron

Question 4

How do oligodendrocytes make the myelin sheath

Answer 4

The phospholipid membrane wraps around the axon,
This creates a fatty layers that prevents signals from passing through

Question 5

What is the function of Astrocytes

Answer 5

Structural support of neuron

Question 6

What is the function of Microglia

Answer 6

Cellular clearance after injury

Question 7

Describe how the signal gets transmitted across the synapse**

Answer 7

Action potential sent down the axon
Cause Ca2+ ion channels to open, causing an influx of calcium into the cell
Triggers the release of neurotransmitters from the vesicles to the synaptic cleft
Neurotransmitters diffuse over the synapse
Bind to post synaptic receptors

Question 8

How to excitatory neutrons change the resting potential

Answer 8

Add a more positive charge

Question 9

Describe action potential generation***

Answer 9

• A stimulus distrusts the membrane, cause Sodium to enter the cell (stretch mediated)
• Resting potential meets threshold - opens Voltage Gated sodium channels, cause an influx in Na+ ions - depolarises the membrane.
• eventually K+ ion channels open, so K+ leaves the cell - repolarises the membrane
• K+ ion channels are slow closing so the cell will reach hyperpolarisation (voltage falls below resting potential)
• Na+ K+ pump brings membrane back to resting potential

Question 10

How is there a net negative resting potential

Answer 10

Sodium potassium pump, pumps more sodium out the cell than potassium in

Question 11

Why is action potential propergation unidirectional

Answer 11

Potassium channels are opened after AP is generated, so AP cannot be triggered as Voltage gated Na+ channels are closed (can’t be opened as cell has incorrect voltage)

Question 12

What is the refractory period

Answer 12

Time where a new action potential cannot be produced in the cell

Question 13

What is temporal summation

Answer 13

Frequency of action potentials increase to increase the intensity of the stimulus

Question 14

What is spatial summation

Answer 14

Multiple neutrons secrete neurotransmitters to o me post synaptic membrane