L12-13 Excitable Cells CNS / PNS Flashcards
The human nervous system can be divided based on structure into the…
Central and the Peripheral Nervous Systems (CNS and PNS)
The CNS comprises…
The brain and spinal cord
The PNS comprises…
All nerves other than brain and spinal cord
The human nervous system can be divided based on function into (3)…
- Sensory receptors (sensory neurons in PNS)
- Integration (in the CNS)
- Effectors (motor neurons in PNS)
Motor neurones are also known as…
Efferent neurones (efferent meaning conduction outwards or away from something)
Interneurones and motor neurones are ( uni / multi / psuedo-uni / bi ) polar
Multipolar
meaning multiple dendrites emanating from the cell body
Motor neurones feature myelination of the axon and a cell body…
At one end
Interneurones have the cell body in the…
Middle
Sensory neurones are also known as…
Afferent neurones (afferent meaning conduction into or towards something)
Sensory neurones can be either…
Psuedo-unipolar (single process which look like 2) or Bipolar (two processes)
All types of neurone share the same basic properties:
- They conduct electrical impulses along the plasma membrane
- Communicate by synapse
- Do not divide
Which of the basic properties of neurones is responsible for neurodegenerative diseases?
They do not divide
Neurones have a ( high / low / average ) metabolic rate
High
An action potential is an ( all-or-nothing / variable ) signal
All-or-nothing
Graded potentials occur over ( the same / longer / shorter ) distances as action potentials
Shorter
Graded potentials are ( like / unlike ) action potentials in that they ( maintain / lose / gain ) strength the further they travel
- Unlike action potentials
* Lose strength the further they travel
The two types of electrical signals in neurones are…
Graded potentials and action potentials
Graded potentials ( never / sometimes / always ) generate action potentials…
Sometimes
if depolarisation at the axon hillock is sufficient
Where in the neurones do graded potentials occur?
a) Dendrites, cell body, axon terminals and axons
b) Dendrites
c) Cell body, axon terminals and axons
d) Dendrites, cell body and axon terminals
d)
graded potentials do not occur in the axon
The post-synaptic electrical impulse is a (graded / action ) potential
Graded
The post-synaptic electrical impulse in muscle cells is known as an…
End-plate potential (EPP)
Graded potentials can be (2)…
Depolarising or Hyper-polarising