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Term IV: Neuro > Brain Cells > Flashcards

Flashcards in Brain Cells Deck (20):
1

Two cell types in nervous system

Neurons and glia

2

Three functions of myelin sheath:

- speeds action potential
- decreases metabolic demands
- decreases space requirements to propagate action potential

3

Three morphologies of neurons and example of where they exist:

- Bipolar: single axon and single dendrite emerging from opposite ends of soma (retinal ganglion cell)
- Pseudo-unipolar: dendrite and axon emerge from same process (DRG)
- Multi-polar: more than two dendrites (spinal motor neuron)

4

Two types of multipolar neurons:

- Golgi I = neurons with long axons
- Golgi II (granule neurons) = neurons with short, locally projecting axons

5

Most neurons, whether sensory, motor, interneuronal, or neuroendocrine, have 4 functional components in common:

Which are functions of dendrites and soma?

1. Input component (excitatory or inhibitory)
2. Integrative component
3. Conductive component
4. Output component

1&2

6

Synapses occur at which dendritic structure?

Spines

7

T or F. A spine receives a SINGLE synaptic input.

FALSE - a single spine has multiple synapses

8

Where does Action potential initiation occur

Axon hillock

9

What appears first during neuronal differentiation? Dendrites or axons?

Axons, then dendrites

10

What do we have more of: glia or neurons?

Glia - 1-5x more than neurons

11

What glial cells form myelin?

Oligodendrocytes and Schwann cells

12

What glial cells are macrophages of the brain that scavenge and remove debris after injury, disease, and neuronal death?

Microglia

13

What glial cells guide migrating neurons and direct outgrowth of axons?

Radial glia

14

What glial cells participate in formation and maintenance of blood-brain barrier?

Astrocytes

15

T or F. Glial cells fire action potentials.

FALSE

16

What glial cells take up neurotransmitters like glutamate to regulate synaptic transmission?

Astrocytes

17

What glial cells buffer K+ concentrations in CNS?

Astrocytes

18

Name the 4 types of microglia.

- Amoeboid - present during development, phagocytose debris, do not present Ag
- Ramified - common morphology of resting microglia
- Activated - phagocytic and Ag presenting
- Gitter cells - full of debris, unable to phagocytose any more material

19

Where do ion channels cluster in axons?

Nodes of Ranvier

20

Myelinating Schwann cells ensheathe _____ axon.

Non-myelinating Schwann cells ensheath ______ axons.

One

Many