First listen to the presentation: Nervous and sensory systems
1. Protective layers of the brain
What is the collective name for the protective layers of the brain? What are they each called?
Answer: The Meninges; pia mater; arachnoid mater; dura mater.
2. Fluid in the brain
What fluid is found in brain and spinal column? Where is this found in the brain? State two functions of this fluid.
3. The neurone
Name the main features of the neurone.
Answer: cell body; axon; dendrites; axon terminals (could include myelin sheath).
4. The action potential
Explain what happens in an action potential.
Answer: sodium ions flood into the nerve cell; the membrane potential is reversed (becomes positive); the action potential is transmitted along the cell (saltatory conduction); the sodium ions are pumped out and the resting potential is restored.
5. The synapse
What happens at a synapse?
Answer: nerve impulse arrives at pre-synapse; chemical (acetly choline) released into synaptic space; action potential triggered post-synapse; chemical is broken down and reabsorbed .
6. Saltatory conduction
Explain saltatory conduction.
Answer: tales place in myelinated nerves; faster than in unmyelinated nerves; depends on Nodes of Ranvier; action potential 'jumps' from node to node (ie Nodes of Ranvier).
7. Regions of the brain
Name the eight regions of the brain (half mark each).
Answer: frontal; motor cortex; sensory cortex; parietal lobe; temporal lobe; occipital lobe; cerebellum; brain stem.
8. Cranial nerves
What do cranial nerves mainly do?
Answer: eye movement; swallowing; smell; hearing.
9. Divisions of the nervous system
Name the two divisions of the peripheral nervous system and the sub-divisions of the division concerned with involuntary actions.
Answer: somatosensory and autonomic; and the autonomic is divided into the sympathetic and the parasympathetic systems.
10. Special senses
In addition to sight what are the other special senses?
Answer: hearing; touch; taste and smell.
11. The eye
What four structures of the eye does light have to travel through to reach the optic nerve?
Answer: cornea; aqueous humour; lens; vitreous humour.
What are the three bones of the inner ear and what are they called, collectively?
Answer: maleus; incus and stapes; ossicles.