FREE AND STUDY GAMES ABOUT PHYSIOEX EX3ACTVY7

PDF Download

FREE AND STUDY GAMES ABOUT PHYSIOEX EX3ACTVY7

EXAM QUESTIONS

Actual Qs and Ans Expert-Verified Explanation

This Exam contains:

-Guarantee passing score -17 Questions and Answers -format set of multiple-choice -Expert-Verified Explanation

Question 1: What is the effect of axon diameter on conduction velocity?

Answer:

The larger the axon diameter, the greater the conduction velocity.Question 2: What is the effect of the amount of myelination on conduction velocity?

Answer:

The greater the amount of myelination, the greater the conduction velocity.Question 3: The axons from touch fibers are A fibers, and the axons from pain fibers are C fibers. When you stub your toe, which would you expect to perceive first?

Answer:

your toe touching something Question 4: How did the conduction velocity in the C fiber compare with that in the B Fiber?

Answer:

C fiber conduction was slower than B fiber.

Question 5: Action potential conduction velocity is fastest in which of the following fibers?

Answer:

A fibers (large diameter, heavily myelinated)

Question 6: How are myelin sheaths separated?

Answer:

by gaps called nodes of Ranvier

Question 7: What is myelination?

Answer:

special wrapping of the membrane from glial cells around the axon Question 8: Why did you need to change the timescale on the oscilloscope for each axon?

Answer:

This is necessary in order to see the action potentials. The velocity changes so when it gets very slow you need a longer time scale.

Question 9: Why does propogation/conduction occur?

Answer:

B/c there are voltage gated sodium and potassium channels located along the axon & b/c the large depolarisation that constitutes the action potential easily brings the next region of the axon to threshold.

Question 10: What influences the conduction velocity of an axon?

Answer:

axon diameter & amount of myelination

Question 11: How can conduction velocity be calculated?

Answer:

By knowing the distance the action potential travels and the amount of time it takes Question 12: Action potential conduction velocity is slowest in which of the following fibers?

Answer:

C fibers

Question 13: How did the conduction velocity in the B fiber compare with that in the A Fiber?How well did the results compare with your prediction?

Answer:

B fiber conduction was much slower than A fiber Question 14: Why did the time between the stimulation and the action potential at R1 differ for each axon?

Answer:

The time between the stimulation and the action potential at R1 differed for each axon because the axon diameter and amount of myelination varied for each axon.Question 15: What are the names of the glia that wrap around the axons in the CNS and PNS?

Answer:

CNS: Oligondendrocytes

PNS: Schwann Cells

Question 16: Why did the timescale have to be changed to measure the conduction velocity of the C fibers?

Answer:

The total time shown on the oscilloscope would have been too short to see the action potential at R2.

Question 17: What happens once the action potential is generated? (2)

Answer:

It is propagated or conducted down the axon. This propagation ensures that the amplitude of the axon does not diminish as it is conducted along the axon.