The document summarizes key information from an anatomy and physiology weekly newsletter, including:
1. It describes the organization of the nervous system into the central and peripheral nervous systems.
2. It provides two articles summarizing nerve impulses and the synapse.
3. It lists the main cell types in the nervous system that help send out impulses to move the human body.
4. It describes a student lab that measured the speed of voluntary kicks versus reflexes using an EKG sensor. The students were able to answer questions about their findings.
4. Reflex Arc Lab
ANATOMY AND Some of our writers got the chance to go to a local high school and watched as
PHYSIOLOGY they did a lab on neuromuscular reflexes. They used an EKG sensor to compare
WEEKLY the speed of voluntary vs a reflex muscle action and to measure the speed of the
impulse. Here is the information that they collected!
Table 1
An special Kick 1 Kick 2 Kick 3 Kick 4 Kick 5 Average
collaboration with Time of 1.7 4.17 6.66 9.12 22.62 8.856
muscle
students from NISD contraction
(s)
Time of 1.29 3.77 6.39 8.82 22.11 8.476
stimulus (s)
Change of T 0.41 0.4 0.27 0.30 0.51 8. 666
(s)
How much do Table 2
Reflex 1 Reflex 2 Reflex 3 Reflex 4 Reflex 5 Average
you know about Time of 6.06 9.67 16.87 20.69 25.84 15.83
muscle con-
Reflexes? traction (s)
Time of 5.59 9.32 16.67 20.08 25.38 15.43
stimulus (s)
Change of T 0.47 0.35 0.20 0.61 0.46 15.63
(s)
Reflex without reinforcement Reflex with reinforcement
Table 3
Reflex re- Max (Mv) Min (mV) Change of Max (mV) Min (mV) Change of
sponse mV Mv
1 1.632 0.834 0.798 2.478 0.594 1.884
2 1.982 0.748 1.234 2.660 0.481 2.179
3 1.565 0.838 0.727 1.430 0.852 0.578
4 1.572 0.801 0.771 1.231 0.890 0.341
5 1.836 0.583 1.253 2.533 0.641 1.892
Average 1.718 0.761 0.957 2.066 0.691 1.375
After the lab was completed the students were able to answer some questions, here are
their answers! 1.) The contraction wasn’t as high in the voluntary activation as in the in-
voluntary activation because you were voluntarily contracting your muscle. 2.) 0.097 m/s
Put together is the speed at which the stimulus traveled in Agron’s leg. 3.) What could account for the
differences is the measurements of the person, having the electrodes not directly on the
by—Ashley B. nerves and the force of the hit from the hammer could differ. 4.) The speed of a nerve
impulse is a lot slower than the speed of electricity because it has many things to go
through within the body while electricity in a copper wire just goes straight from end to
end with no interruptions. 5.) The size of a person can effect the time it takes for the
nerve pulses to get to the brain.
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