Nervous Tissue Structure And Function: Flashcards
What type of neurones does the peripheral nervous system contain?
Sensory and motor neurones
What type of neurones does the CNS contain?
Relay neurones
Describe the distribution of grey and white matter in the brain and in the CNS:
- White matter central in brain. Grey matter peripheral in brain.
- White matter periferal in spinal cord. Grey matter central. (Butterfly shaped).
What connects the ventral horns to the dorsal horns?
Grey commissure.
Which parts of the axon lie within the CNS and which parts lie in the PNS?
- The main cell body, dendrites (cytoplasmic projections) and the proximal part of the axon lie in the CNS.
- The distal part of the axon lies in the PNS.
What are the 4 types of neurones?
- sensory
- motor
- integrative
- anaxonic
Describe the location and function of motor and sensory neurones:
Motor:
Location: CNS to periphery.
Function: to send signals to effector tissues.
Sensory:
Location: Periphery towards CNS.
Function: to send environmental signals to integrative centre e.g. pain signals to brain.
Describe the location and function of the integrative and anaxonic neurones:
Integrative:
Location: CNS
Function: collate all info
Anaxonic: (no axon).
Location: retina (some parts of CNS).
Function: To act as relays.
What are the majority of the nerves within the CNS?
- interneurones
What are the 5 different types of synapses:
- axosomatic
- axodendritic
- axoaxonic
- dendro-dendritic
- axo-axonal
What is an axosomatic synapse?
- direct to plasma membrane of nerve/cell.
What is an axodendritic synapse?
- axon terminal synapses with a dendritic spine.
What is an axoaxonnic synapse?
- synapse at the axonic bouton (knob). May enhance or inhibit the original synapse.
What is the function of an ependymal cell?
- Synthesises and secretes cerebrospinal fluid and cilia on the surface of these cells move CSF from the ventricles to the spinal cord.
What are some symptoms of MS?
- fatigue
- vision problems
- slurred speech
- numbness and tingling sensations.
- mobility issues.
- urinary retention
- constipation
What causes MS?
- autoimmune degradation of the myelin sheath.
- its a remitting and relapsing disease.
What is the perkaryon?
- The cell body of a neurone (containing a nucelus).
In the sympathetic and parasympathetic nervous systems which part of the neurone is normally short and which part is normally long? Where do both of the neurones synapse?
Sympathetic:
- pre-ganglionic is short. Post ganglionic is long.
- synapses near the vertebral column.
Parasympathetic:
- pre-ganglionic is long. Post ganglionic is short.
- synapses close to or in wall of target tissue.
In the autonomic nervous system ( sympathetic and parasymppathetic), which neurone is myelinated and which is unmyelinated?
- pre-ganglionic is myelinated.
- post-ganglionic is unmyelinated.
Which neurotransmitter is used for the sympathetic and parasympathetic nervous systems?
- sympathetic - noradrenaline.
- parasympathetic - Ach
