Astrocytes and Neurones

Question 1

What is MAP2B - what is its function?

Answer 1

A microtubule stabilising protein

Question 2

List some somato-dendritic specific components

Answer 2

• MAP2B - microtubule stabilising protein
• PSD scaffolding (post-synaptic density)
• Meurotransmitter receptors
• Signalling proteins

Question 3

What are the different morphologies of dendritic spines?

Answer 3

1. Stubby
2. Spine thin
3. Mushroom
4. Filopodium

Question 4

How do dendritic spines indicate signal strength?

Question 5

What is one cellular adaption of dendritic spines with regards its organelles?

Answer 5

• Many mitochondria due to high energy requirement

Question 6

Where do axons emerge?

Answer 6

From the axon hillock at the soma of the neurone

Question 7

What are some cellular adapation of neurones with regards its organelles?

Answer 7

• Lots of prominent microtubules and neurofilaments for transport of proteins
• Lots of mitochondria to maintain RMP

Question 9

What are the 2 main morphologies of pre-synaptic terminals?

Answer 9

1. Boutons
2. Varicosities - mainly found at NMJ

Question 10

What are primary and secondary dendrites?

Answer 10

• Primary dendrites - directly go into soma
• Secondary dendrites branch from the primary dendrites

Question 11

What are the 3 main effectors that neurones synapse onto?

Answer 11

1. Other neurones
2. Mucle cells at the NMJ
3. Glandular cells

Question 12

When neurones synapse onto other neurones, at what point on them do they synapse - what are the 3 types of connections - and are these typically excitatory or inhibitory?

Answer 12

1. Axo-dendritic - Excitatory
2. Axo-somatic - Inhibitory
3. Axo-axonic - Inhibitory

Question 13

What does the term neuronal integration mean?

Answer 13

This denotes the idea that the post-synapetic neurone integrates the competing excitatory and inhibitory signals from the various pre-synaptic connections including axo-dendritic, axo-somatic and axo-axonic

Question 14

1) Why are excitatory and inhibitory neurotransmitters so-called?
2) Give 2 examples of each excitatory and inhibitory neurotransmitters

Answer 14

1)

Excitatory neurotransmitters increase the chance of depolarisation and therefore an action potential being transmitted and v.v.

2)

EXCITATORY - GABA, Dopamine

INHIBITORY - Glutamate, ACh

Question 15

Give 2 modes of diversity of signals at the synapse

Answer 15

1. Diversity in neurotransmitter
2. Diversity in receptors for each neurotransmitter - e.g. there are 11 glutamate receptor proteins, 3 GABA receptors, 5 dopamine receptors and 14 5-HT receptors