Phys Quiz 2

Question 1

Resting membrane potential (RMP)

Answer 1

Negative -75mv

Question 2

Depolarization

Answer 2

Inward movement of positively charged ions (Na+)

Question 3

Repolarization

Answer 3

Immediately follows depolarization. Returns membrane to its resting potential- the outward movement of positively charged ions (K+)

Question 4

Action Potential

Answer 4

Signaling events for neuron communication or muscle contraction

Responds to a threshold- and then spreads through the entire length of the neuron axons

Question 5

Excitation- Reaction Coupling

Answer 5

Conversion of electrical signals (action potentials) to mechanical events (muscle contraction)

Question 6

Muscle Twitch

Answer 6

Stimulation causes a quick cycle of contraction and relaxation

Question 7

Latent Period

Answer 7

Between the onset of the stimulus and the beginning of tension production

Question 8

Contraction Period

Answer 8

The muscle develops external tension that can be recorded by a force transducer

Question 9

Relaxation Period

Answer 9

Muscle loses tension until it is back to pre-twitch levels

Question 10

Relation between clench force and EMG

Answer 10

More force is used- more neurons r required- more muscle cells are used- more electricity is generated.

Question 11

Command Fatigue

Answer 11

Rapid decline

Question 12

Subject trying hard- excitation-contraction failing

Answer 12

Slow decline

Question 13

Factors influencing fatigue

Answer 13

Energy availability and strength conditioning

Question 14

Threshold

Answer 14

The smallest stimulus that gives a visible twitch

Question 15

Subthreshold

Answer 15

Smaller value than the threshold

Question 16

Suprathreshold

Answer 16

Anything of a larger magnitude than the threshold

Question 17

stimulus frequency

Answer 17

rate of action potentials