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Flashcards in Nervous Tissue Deck (34):
1

Function of the nervous system

Allows rapid communication between widely spaced parts of the body by the action of specialised cells called neurones which gather and process information and generate a response

2

Functional cell type of the nervous system

Nerve cell or neurone

3

Neurones

Receive information and transmit electrical impulses to another neurone or effector cell

4

Glial cell types

Astrocytes, oligodendrocytes, microglia and ependymal cells

5

Astrocytes

Many numerous processes
Support, maintaining the blood-brain barrier and environmental homeostasis

6

Oligodendrocytes

Produce myelin in the CNS (NOT PNS)

7

Microglia

Similar lineage to macrophages
Immune monitoring and antigen presentation

8

Ependymal cells

Cuboidal/columnar epithelium that lines the cavities in the CNS such as the ventricle
Typically cillliated

9

A group of neurones living outside the CNS

Ganglion

10

Characteristics of neurones

Cell body contains nucleus and most of cell organelles
Long process - axon - transmits data from the neurone to other cells
Numerous short processes - dendrites - increase surface area avalible for connections
Specialised junctions - synapses - between axon and other cells to allow communication

11

3 groups of neurones

Multipolar, bipolar and psuedopolar

12

Axon arises from a swelling

Axon hillock

13

Nerve cell body

Abundant RER, free polyribosomes and Golgi apparatus in the body but not in the axon

14

Axonal transport

Energy consuming mechanism to move material up and down the axon

15

How does axonal transport work

Uses molecular motors - kinesin- which use microtubules as a railway track to haul attached organelles and vesicles

16

Types of axonal transport

Fast axonal transport and slow axonal transport

17

PNS consists of

Nerves and ganglia and includes elements of the somatic and autonomic nervous systems

18

Ganglia are composed of

Neurone cell bodies, support cells, axons and loose fibrocollagenous tissue

19

What are the support cells of the PNS

Satellite cells and schwann cells

20

What are the two types of nerve ganglia

Dorsal root ganglia and autonomic ganglia

21

Peripheral nerve is composed of

Axons, schwann cells, fibroblasts and blood vessels

22

Connective tissue of peripheral nerve

Epineurium - surrounds the whole nerve
Perineurium - surrounds a fascicle
Endoneurium - surrounds individual nerve fibres

23

Where are unmyelinated axons found

In the clefts in the cytoplasm of schwann cells

24

What is the myelin sheath formed by in the PNS

Schwann cells

25

Each schwann cells creates myelin for

A single axon

26

What produces myelin in the CNS

Oligodendrocytes

27

Oligodendrocytes makes myelin sheath for

Many axons

28

In there connective tissue in the CNS

No

29

What are the spaces in the myelin sheaths called

Nodes of Ranvier

30

What does the nodes of Ravier allow

For the action potential to jump along the axon increasing the speed of conduction

31

Grey matter

Huge number of neurones, cell processes, synapses and support cells

32

White matter

Axons and their support cells

33

Neuropil

A mat of neuronal and glial cell processes that occupies much of the grey matter

34

Synapses

Come in many forms
Vesicles in the end contain neurotransmitters that are released in response to an action potential