5 Written Questions
5 Matching Questions
- In regards to active propagation, describe what occurs.
- Describe the epineurium
- Where are the cell bodies of motor neurons located
- What is passive propagation responsible for?
- Describe the anatomy of a nerve.
In the ventral horn.
Sheath covering the entire nerve, contains nutrient blood vessels.
- d Sensory function, cell-to-cell communication & impulse modulation.
- e Once an action propagation is initiated in 1 region of a neuron, the depolarization "wave" will spread out sequentially to the rest of the neuron.
5 Multiple Choice Questions
- Contains the nerve fibers in fascicles, semipermeable, acts as a major barrier to diffusion of LAs (tight junctioned).
- Myelinated, preganglionic autonomic
- Na & K channels are closed but K channels leak (100x more leaky than Na channels) Na K ATPase restores ionic gradients.
- Travel as a uniform wave of depolarization d/t conformational changes in ion channels.
- Unmyelinated, postganglionic autonomic
5 True/False Questions
Describe depolarization & action potential of a nerve. → Must hit threshold (point at which the cell will become fully depolarized)
Once threshold reached, Na channels open rapidly, the cell becomes positive (depolarized).
How does the body send signals over long distances? → Decreases capacitance (decreases the loss of electrical signal).
Describe impulse firing threshold → Point where the balance of ionic currents reverses from ATP requiring polarization to gradient dependent depolarization.
Describe membrane threshold → That point in the process of depolarization when continued stimulation leads to complete action potential.
Describe the hyperpolarization phase (refractory period) → The membrane potential becomes transiently more negative than the normal resting potential. Refractory period makes the axon unidirectional.