What has happened in the muscle when the maximal stimulus is achieved? ... Cross bridge cycle and when the muscle tension exceeds the load, muscle shortening happens . The latent period increases as the weight of the load gets heavier, this is for the necessary force to be generated by the muscle.
What was happening to the muscle cells within the muscle as the stimulus voltage was increased?
As the intensity (voltage) of the stimulus is increased above the threshold, more and more fibers are stimulated and the response becomes greater and greater . ... This stimulus, called the maximal stimulus marks the point where all of the fibers in the muscle are stimulated and responding all-or-none.
What was the maximal stimulus of the muscle?
Maximal stimulus. The intensity of a stimulus which excites and recruits all motor units within a muscle . Any further increase in the stimulation does not produce a greater muscular contraction.
What happens in the muscle when the threshold stimulus is applied?
Increasing the stimulus voltage on isolated skeletal muscle increases the amount of active force produced by the muscle . This happens because more fibers and motorneurons are activated and leads to an increase in muscle force. ... All muscle fibers are recruited by the motor neurons to generate maximal force.
What happens to the muscle as a whole when the frequency of stimulus increases when the strength of the stimulus increases?
Increasing the stimulus frequency lead to an increase in active force generated by the whole skeletal muscle. Active force began to pleatu and maximal tetanic tension occurred.
Why is Supramaximal stimulus used?
To obtain reproducible results, researchers usually use supramaximal stimuli, which will induce contraction of all the fibers at each stimulation . Supramaximal stimulation is stimulation having intensity (voltage or current) significantly above that required to activate all the muscle fibers.
What happens if a muscle receives a stimulus not quite as strong as its threshold?
We begin with a low amount of stimulation that does not reach the threshold to produce a contraction. The muscle fiber will respond by remaining relaxed , it will not contract. Now if we increase the stimulation so that enough is produced to reach the threshold the muscle fiber will respond by contracting.
What is the threshold stimulus for muscle contraction?
The minimum strength required for the stimulus to initiate the response of muscle contraction is known as the threshold stimulus. No response is seen if the magnitude of the stimulus is below this threshold value. The sliding filament theory explains the contraction of muscles when the threshold stimulus is achieved.
Which weight did the muscle contraction move the greatest distance?
Which weight did the muscle contraction move the greatest distance? You correctly answered: 0.5-g weight .
What are the two most important pathways by which ATP is generated in muscle cells?
Glycolysis converts glucose to pyruvate, water and NADH, producing two molecules of ATP. Excess pyruvate is converted to lactic acid which causes muscle fatigue. Cellular respiration produces further molecules of ATP from pyruvate in the mitochondria.
Which would be the correct order for skeletal muscle contraction?
Depolarisation and calcium ion release. Actin and myosin cross-bridge formation. Sliding mechanism of actin and myosin filaments. Sarcomere shortening (muscle contraction)
Why is there a latent period for muscle contraction?
The first phase is the latent period, during which the action potential is being propagated along the sarcolemma and Ca ++ ions are released from the sarcoplasmic reticulum. This is the phase during which excitation and contraction are being coupled but contraction has yet to occur.
Why didn’t a finger twitch occur at a lower stimulus current?
Why didn’t a finger twitch occur at a lower stimulus current? ... Above a certain stimulus current, the amplitude of the finger twitch no longer increases .
What is the difference between stimulus frequency and stimulus intensity?
1. What is the difference between stimulus intensity and stimulus frequency? The stimulus intensity is the electrical changes that relate to the action potential . The Page 2 Copyright © 2014 Pearson Education, Inc. frequency is the number of action potentials per minute.
What was the effect of increasing the frequency of stimulation?
On the other hand, at increasing frequency of stimulation the influence of the initial low-frequency stimulation can depress the tension-time area . The decreasing rate of stimulation during relaxation appeared to support the tension more effectively in slow-twitch motor units than in fast ones.
What happens when you increase the frequency of stimulation?
If you increase the frequency of stimulation you can increase the amount of muscle tension developed in a muscle fiber .
