disorders of the nervous system

Question 1

alzheimer’s: causes

Answer 1

characterised by a loss of neurons and synapses in the cortex of the brain, as well as the presence of amyloid plaques and tangled bundles of fibres.

Question 2

alzheimer’s: symptoms

Answer 2

loss of brain function results in slower thinking, behaviour changes, confusion about events, time and place, and leads to severe memory loss. patients may not recognise people they used to know, and find it hard to speak, swallow and walk.

Question 3

multiple sclerosis: causes

Answer 3

thought to be caused by an individual;s immune system attacking the nervous system. an unknown trigger activates helper T-cells. They have antigen-specific receptors that recognise CNS myelin as an antigen. The activated T-cells release cytokines and adhesion molecules that enable them to bind to and destroy myelin fragments on microglial cells.

Question 4

multiple sclerosis: symptoms

Answer 4

symptoms depend on location of the plaques in the brain and/or spinal cord. Each sufferer has an unpredictable, different set of symptoms depending on which part/s of the CNS is most affected.