Nervous Tissue and Neurodegenerative Disorders Flashcards
1
Q
Properties of neurones
A
- irritability
- receptors
- conductivity
- impulses
- 3 parts (dendrites, cell body, axon)
2
Q
Cell body (of neurone)
A
- Nissl bodies (clusters of free ribosomes and rER)
- cytoskeleton (neurofibrils: microtubules and neurofilaments)
- no centrioles
3
Q
Dendrites
A
- branched
- location of synapses
4
Q
Axon
A
- cylindrical projection
- one per neurone
- specialised to conduct action potentials
- contains mitochondria and cytoskeletal proteins
5
Q
Neuroglia
A
-smaller than neurones but more numerous
6
Q
CNS
A
- astrocytes
- microglia
- ependymal cells
- oligodendrocytes
7
Q
PNS
A
- satellite cells
- schwann cells
8
Q
Astrocytes (CNS)
A
- star shaped
- maintain chemical environment
- blood-brain barrier
- provide nutrients to neurones
9
Q
Microglia (CNS)
A
- small
- protects the CNS by phagocytosis of invading microbes
- clear away debris of dead cells
10
Q
Ependymal (CNS)
Line cerebrospinal fluid-filled cavities
A
- Epithelial cells which line the ventricles of the brain and central canal of the spinal cord
- form cerebrospinal fluid (CSF)
- cilia encourage movement of CSF
- monitor composition of CSF
11
Q
Oligodendroytes (CNS)
dendrite-like processes
A
- Structural support, scaffolding
- forms myelin sheath for some CNS cells
12
Q
Schwann Cells (peripheral nervous system)
A
- wrap spiral around axons of motor nerves
- collectively called the myelin sheath
- makes up WHITE matter
- acts like insulation on a wire
- nodes of ranvier (spaces between)
13
Q
Satellite Cells (PNS)
A
- flattened cells arranged around the cell bodies of neurones
- regulate chemical environment
- involved in repair
14
Q
Tumours
A
-most brain tumours are gliomas
15
Q
Demyelination
A
- Loss or destruction of myelin sheaths
- can lead to paralysis (eg MS)
- can affect vision, speech, balance and motor co-ordination
