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Title: I need help answering these questions. I don't understand labs at all!!! Post by: jramse04 on Apr 16, 2014 Electrical Stimulation
1. Name each phase of a typical muscle twitch, and, on the following line, describe what is happening in each phase. a. b. c. 2. In Activity 2, how long was the latent period? _______________ msec Describe the chemical changes that are occurring during this period. _____________________________ _______________ The Graded Muscle Response to Increased Stimulus Intensity 3. From Activity 3, describe the effect of increasing the voltage. What happened to the force generated and why did this change occur? 4. How does this change occur in vivo? Skeletal Muscle Physiology E X E R C I S E NAME _____________________________ _______ LAB TIME/DATE ________________________ 28 Review Sheet 2 5. In Activity 4, you looked at the effect of stimulating the muscle multiple times in a short period with complete relaxation between the stimuli. Describe the force of contraction with each subsequent stimulus. _____________________________ __________________ 6. Describe the chemical changes that are thought to correlate to this change in vivo. 7. In Activity 5, what was the effect of increasing the frequency of stimulation? 8. Compare and contrast wave summation with recruitment (multiple motor unit summation). How are they similar? How was each achieved in the simulation? 9. Explain how wave summation and recruitment are achieved in vivo. 10. For Activity 6, explain how you were able to achieve smooth contraction at a given force level. ______________________ 11. In Activity 7, explain why the force of the muscle decreased over time during uninterrupted stimulation. Describe the multiple causes of this phenomenon, which occurs in vivo with prolonged use of a muscle. __________________________ Isometric Contraction 12. In Activity 8, at what length of the muscle does the passive force start to increase? 13. Explain what happens to the active force with an increase in the muscle length. 14. Explain what happens to the active force with a decrease in the muscle length. 15. Explain what is happening in the sarcomere that results in the changes in total force when the muscle length changes. ________ Isotonic Contraction 16. In Activity 9, which weight resulted in the highest initial velocity of shortening? 17. Explain the relationship between the amount of resistance and the initial velocity of shortening. 18. Explain why it will take you longer to perform 10 repetitions lifting a 20-pound weight than it would to perform the same number of repetitions with a 5-pound weight. _____________________________ _____________________________ ____ Review Sheet 21 29 Title: Re: I need help answering these questions. I don't understand labs at all!!! Post by: padre on Apr 17, 2014 Doesn't seem like you attempted any of these :-\
https://biology-forums.com/index.php?topic=3161.0 Title: Re: I need help answering these questions. I don't understand labs at all!!! Post by: jramse04 on Apr 17, 2014 Yes I have. I have about 4 questions answered right now, but it's hard for me to get them answered because I didn't even understand the lab
Title: Re: I need help answering these questions. I don't understand labs at all!!! Post by: padre on Apr 17, 2014 That's no excuse, you're an adult!
13. Explain what happens to the active force with an increase in the muscle length. Active force increases until the optimal length is obtained, then decreases as muscle length continues to increase beyond optimal length. 14. Explain what happens to the active force with a decrease in the muscle length. Active force decreases as muscle length decreases. The rest is on you, unless you start following forum rules and post two questions per thread. |