Biology 241 - Accelerated General Human Physiology » Summer 2021 » Lab Q11

Need help with your exam preparation?

Existing Quiz Clients Login here
Question #1
During the skeletal muscle simulation, a low-voltage electrical stimulus (0 or 0.1 volts) produced no response on the screen because:
A.   the stimulus must produce many action potentials in the muscle fibers to evoke a contraction.
B.   the evoked action potential was too small to produce a visible contraction.
C.   the stimulus did not stimulate any muscle fibers to threshold.
D.   the muscle contraction was too small to register.
Question #2
The latency period is the time:
A.   taken for a skeletal muscle to contract and relax.
B.   period between stimulation and the shortening of the skeletal muscle.
C.   period when the level of calcium in the cytoplasm is greater than at rest.
D.   when cross-bridge cycling is taking place and the muscle is shortening.
Question #3
When the muscle had weights attached and trying to contract, what was happening during the latency period:
A.   there was no tension in the tendon.
B.   the muscle was contracting isometrically.
C.   the muscle was lifting the weight.
D.   the muscle was not contracting.
Question #4
According to the Length-Tension relationship, maximum tension is produced in a skeletal muscle fiber when it is:
A.   at or near resting length
B.   shorter than resting length
C.   tension is constant at all muscle lengths
D.   longer than resting length
Question #5
During incomplete tetanus, the amount of tension increases above that seen with a single twitch because:
A.   sarcoplasmic calcium levels drop.
B.   there is accumulation of calcium in the sarcoplasm.
C.   maximum tension is achieved.
D.   the muscle twitches fuse into a single, maximum contraction.
Question #6
Why would the rate of muscle relaxation be slower after tetanus than after a single twitch?
A.   The contraction was larger, so the rate of relaxation would be slower.
B.   It takes time for the large amount of calcium in the sarcoplasm to be taken up by the sarcoplasmic reticulum.
C.   There is maximum amount of overlap between the thick and thin myofilaments.
D.   Cross-bridges are formed during relaxation.
Question #7
Match the terms with its definition. muscle twitch
A.   muscle response from a single action potential
B.   declining muscle force during a sustained contraction
Question #8
Match the terms with its definition. tetanus
A.   maximum muscle force
B.   muscle response from a single action potential
Question #9
Match the terms with its definition. latent period
A.   maximum muscle force
B.   time between action potential stimulus and muscle activation
Question #10
Match the terms with its definition. motor unit
A.   time between action potential stimulus and muscle activation
B.   a single motor nueron and all the muscle fibers it innervates
Question #11
Match the terms with its definition. recruitment
A.   adding more muscle units to complete a task
B.   a single motor nueron and all the muscle fibers it innervates
Question #12
Match the terms with its definition. fatigue
A.   declining muscle force during a sustained contraction
B.   adding more muscle units to complete a task
Question #13
The electromyogram (EMG) records:
A.   tension in the contracting muscle.
B.   electrical activity from the lower motor neurons.
C.   electrical activity from the contracting muscle fibers.
D.   the movement of the contracting muscle.
Question #14
If the peak-to-peak amplitude of the EMG is an indication of the number of muscle fibers contracting, an increase in dynamometer pressure was produced by:
A.   fewer muscle fibers contracting.
B.   the same number of muscle fibers contracting.
C.   more muscle fibers contracting.

Need help with your exam preparation?

Existing Quiz Clients Login here