L5 Neural Tissues

Question 1

What is the purpose of the nervous system?

Answer 1

Communication through sensory detection, information processing, motor activity leading to behaviour.

Question 2

What is the central nervous system?

Answer 2

Brain and spinal cord.

Information processing, reflexes and behaviour.

Question 3

What is the peripheral nervous system?

Answer 3

Cranial and spinal nerves.

Sensory detection and motor activation.

Question 4

What is an afferent neurone?

Answer 4

Transmits sensory information to the brain and spinal cord.

Question 5

What is an efferent neurone?

Answer 5

Motor neurone transmit information from the brain to the effector organ.

Question 6

What is a ganglion?

Answer 6

A group of cells outside the CNS (excluding basal ganglia in the brain).

Question 7

What is a motor ganglion?

Answer 7

Autonomic.

Parasympathetic ganglion, Smaller neurones, eccentric nuclei.

Question 8

What is a sensory ganglion?

Answer 8

Dorsal root ganglion.

Big neurones with central nuclei.

Question 9

What are Brodmann Areas?

Answer 9

Numeric (1-52) regions of the cortex with particular inputs and outputs.
4 primary motor cortex
17 primary visual cortex

Question 10

What defines a CNS neurone?

Answer 10

Nucleus within cell body and extends one or more processes.

Question 11

What is myelin?

Answer 11

Wraps around to electrically insulate the axon, made of many layers of cell membrane, and increase conduction velocity.

Question 12

What is a multipolar neurone?

Answer 12

1 axon, many dendrites.

Question 13

What is a pyramidal cell?

Answer 13

Found in the neocortex with a small axon, linked to thinking.

Question 14

What is a Purkinje cell?

Answer 14

In the cerebellum, dendrites are long with many interactions with other layers.

Question 15

What is a dorsal root ganglion?

Answer 15

Psuedounipolar sensory neurone, found just before the spinal cord. Surrounded by satellite cells.

Question 16

What is a bipolar neurone?

Answer 16

1 dendrite and 1 axon, rare sensory neurones.

Found in the retina.

Question 17

What is pseudounipolar neurone?

Answer 17

1 axon and 1 dendrite, dorsal root ganglion.
2 processes move toward each other and fuse.
Unipolar have no dendrites.

Question 18

What are interneurons?

Answer 18

Inhibitory or excitatory relay neurone, connects dorsal and ventral roots in the spinal cord.

Question 19

How do glia differ from neurones?

Answer 19

No action potentials
Able to divide
Form myelin sheaths
Do not form synapses
Many more glia
Supportive and protective role
Smaller

Question 20

What cells are a common source of tumours in the nervous system?

Answer 20

Glial cells.

Question 21

What is an oligodendrocyte?

Answer 21

Production and maintenance of the myelin sheath in the CNS.

1 myelinates many axons.

Question 22

What is an astrocyte?

Answer 22

Supports and assists a neurone in development and growth (nourishment)
Protects from harmful substances (blood brain barrier)
Controls vasodilatation of local blood vessels (blood flow)

Question 23

What are microglia?

Answer 23

Immune cells, formed from mesoderm
Protect neurones from disease, migrate to injury sits and engulf microbes.
Can develop from monocytes
Quick moving and active

Question 24

What are ependymal cells?

Answer 24

Line brain ventricles and central canal of the spinal cord.
Form cerebrospinal fluid from fluid, electrolyes and salts.
Cilia and microvilli on apical membrane.
Act as epithelium.

Question 25

What are Schwann cells?

Answer 25

Produce and maintain myelin sheath in the PNS, 1 neurone has many Schwann cells.
1 axon per Schwann cell.
Allow PNS regeneration.

Question 26

What are satellite cells?

Answer 26

Support neurones, regulate exchange of materials between neurones and interstitial fluid.
PNS astrocytes.

Question 27

What are the layers of the meninges?

Answer 27

3 meningeal layers:
Dura matter
Arachnoid (thick, contains blood vessels)
Pia matter (like epithelium)

Question 28

What is a glioma?

Answer 28

Largest group of primary tumours, derived from glial cells
Highly malignant
Rapid growth
Hard to fully remove surgically
Inside cranium usually
Poor prognosis unless caught early

Question 29

What is a neuroblastoma?

Answer 29

Common paediatric tumour
Outside the cranium (ie abdomen)
Derived from neural crest cells from sympathetic nervous system (leads to an increase in catecholamines ie noradrenaline)
Good initial prognosis but survival rates and treatment depends on the type
Survivors often develop neurological problems around 30 years later