5 Written questions
5 Matching questions
- Do CNS nerve fibers generally regenerate?
- Is the sodium-potassium pump and active or passive process?
- What is the most immediate effect of application of a threshold stimulus to a nerve fiber membrane?
- Is the resting membrane of a nerve fiber more permeable to sodium ions or to potassium ion?
- How does nerve tissue respond to injury? What cells are responsible for the repair? Where can it occur?
- a In CNS, it doesn't heal.
In PNS, if mylineation cells are still in tact, they will reform a path for the neuron to grow.
Schwann Cells or Oligodendricites
- b ...
- c Active
- d Sodium
- e Not really.
5 Multiple choice questions
- Axonal transport is a cellular process responsible for movement of mitochondria, lipids, synaptic vesicles, proteins, and other cell parts (i.e. organelles) to and from a neuron's cell body, through the cytoplasm of its axon
- Presynaptic - The neuron that sends the action potential to the next dendrite
Postsynaptic - Receives the message
Convergence of Neurons - First one neuron is influenced by many others, resulting in a convergence of input.
Divergence of Neurons - When the neuron fires, the signal is sent to many other neurons, resulting in a divergence of output.
- In order to get back to polarization, they have to pump in 3 Na out, 2 K in
- Neuroglia are cells that support and protect neurons
There are more neuroglia than neurons, they don't have dendrites or axons.
Astrocytes (CNS) - Forms blood brain barrier, protects neurons, allow the exchange of nutrients and waste
Oligodendricites - Mylinate the CNS
Epidymal (CNS) - Circulate the cerebral spinal fluid
Microglia - Eat debris in the CNS
Satellite and Schwann Cells are in the PNS.
5 True/False questions
What principle is applied to transmission of a nerve impulse (action potential)? What is a threshold stimulus? What is the ionic basis for threshold? → Threshold Stimulus is the all or none principle. Resting potential -55mv. Has to bring it positive with K+ ions.
Voltage Gated K+ Ions open up which allows K+ ions to enter the membrane.
What is summation? Temporal and spatial summation result in what? → Certain stimulus happens repeatedly, and adds to threshold in order to get an action potential.
Results in threshold
What is salutatory conduction of an action potential? Does it occur in all nerve fibers? How does diameter of a nerve fiber affect speed of conduction? → Salutatory conduction of an action potential is when you jump from node to node.
Which channels are activated for depolarization in an action potential? → Voltage Gated Na+ Channels
What is membrane permeability? → Only allows certain things through.