Neuron Structure

Question 1

3 parts of neuronal cytoskeleton?

Answer 1

Microtubules
Neural filaments
Microfilaments

Question 2

Microtubule structure/location?

Answer 2

Tubulin diners arranged into hollow tube
Large
Run down neurites

Question 3

Function of microtubules

How are they made and regulated?

Answer 3

Transport (esp down axon where there is no ER (transport organelle))
Microtubule associated proteins

Question 4

Neurofilament structure?

Answer 4

Medium

Question 5

Functions of neurofilaments?

Answer 5

Structural support

Regulate diameter of axons

Question 6

Structure of microfilaments

Answer 6

Small

Actin

Question 7

Function of microfilaments

Answer 7

Connects with pm and microtubules

Question 8

What are neurites

Answer 8

Dendrites + axon

Question 9

Where do densrities receive chemical info

Answer 9

Synapses on dendritic spines

Question 10

What protein is abundant in dendrites?

Answer 10

Actin

Question 11

How can environment and development affect dendritic spines

Answer 11

Affect length and density

Eg. Longer but fewer in mentally retarded individuals

Question 12

3 parts of axon?

Answer 12

Axon hillock
Axon proper
Axon terminal

Question 13

2 types of axon transport?

Answer 13

Fast and slow exoplasmix transport

Question 14

Describe fast exoplasmix transport

Answer 14

1m a day
Anterograde: kinesin takes proteins to the axon terminal (via microtubule)
Retrograde: dynein takes metabolites away from axon terminal

Question 15

Describe slow exoplasmix transport

Answer 15

Mechanism unknown

0.1-10mm

Question 16

3 features of axon terminals?

Answer 16

No microtubules
Lots of vesicles
Lots of membrane proteins, hence mitochondria

Question 17

Synapses consist of

Answer 17

Presynaptic axon terminal
Synaptic cleft
Postsynaptic neuron

Question 18

5 variations in neuron structure?

Answer 18

• length of axon
• neurotransmitter
• number of axons
• shape
• connections

Question 19

Describe variation in neuronal connections

Answer 19

Can be with other neurons, the environment or effectors

Question 20

Variation in neuron shape?

Answer 20

Pyramidal - linear, transmit info

Stellate - collect info

Question 21

Describe variation in number of axons

Answer 21

• unipolar: soma connected to one axon
• bipolar
• multipolar

Question 22

Role of myelinating glia

Answer 22

Schwann cells and oligodendrocytes - create myelin, increasing conduction velocity…

Question 23

Functions of microglia?

Answer 23

Brain immune system
Gifts neural inflammation
Macrophages phagocytise stuff

Question 24

Role of ependymal cells?

Answer 24

Epithelial
Line ventricles
Secrete CSF
FORM choroid plexus which kinds lateral ventricle

Question 25

Role of astrocytes?

Answer 25

Contributes to blood brain barrier
Processes hold oresynaptic and postsynaptix neurons together - take up ions, release modulators
K+ bufferingg