LAB 7: Skeletal Muscle Physiology October 18, 2015 Suzanne Smith (Dunlap) Suzanne Smith (Dunlap) LAB 7: Skeletal Muscle Physiology Purpose The purpose of this lab is to allow the student to gain a be±er understanding of the terms excita²on-contrac²on coupling, electrical s²mulus, muscle twitch, latent period, contrac²on phase, and relaxa²on phase. A simula²on lab that ini²ates muscle twitches with electrical s²muli of varying intensity does this. Addi²onally, the student will iden²fy and measure the dura²on of the latent period. The student will also gain a be±er understanding of how increasing s²mulus voltage to an isolated muscle in this experiment mimics motor unit recruitment in the body as discussed in the text. The discovery of tetanus and fa²gue in isolated skeletal muscles will be brought to a±en²on as well as the rela²onship between the length and tension in comparison with isotonic contrac²ons and the load velocity. Hypothesis My hypothesis is that if the stimulus voltage is increased from 1.0 volt up to 10 volts then The active force will first increase and then plateau at some maximal value as the stimulus voltage increases. Additionally if the stimulus frequency increases, then the muscle force generated by each successive stimulus will first increase and then decrease as the stimulus frequency becomes very high. Alternatively If the stimulator is briefly turned off for defined periods of time, then the length of the rest period will proportionately increase the length of time for sustained muscle tension. Materials: 1. Textbook: Marieb, Human Anatomy & Physiology, 10e, Pearson, (2016) 2. Personal notes made on Chapter 9 3. Macbook Pro and internet access 4. 5. word-processing soFware, such as MicrosoF Word Methods: 1. Collect all necessary materials in order to complete the lab assignment. 2. Review all of professors Blackboard announcements and syllabus for Lab grading criteria. 3. Read the Overview for this lab which is found within the ac²vity on PhysioEx, before you begin. 4. Work through each required ac²vity, including the Objectves, InTroducton , and the Pre-lab Quiz . 5. Choose the ExperimenT tab and read the instruc²ons on the leF of the screen to begin your experiment. . 6. ³ollow the instruc²ons provided throughout each ac²vity to complete this exercise, gathering your data as you proceed. 7. Be sure to choose Record Data aFer EACH por²on of the experiment. 8. When you ´nish gathering data and answering the follow-up ques²on, you will be directed to a screen that shows the data for your lab report; copy this data into the data / analysis sec²on of your lab report. 9. ³rom the PhysioEx screen, select and complete each Review Sheet. Include your responses in the data / analysis sec²on of your lab report with your experimental data. Your lab report should include and summarize ALL of the ac²vi²es in Exercise 2.
Стратмор сидел за современным письменным столом с двумя клавиатурами и монитором в расположенной сбоку нише. Стол был завален компьютерными распечатками и выглядел каким-то чужеродным в этом задернутом шторами помещении. - Тяжелая неделя? - спросила. - Не тяжелей, чем обычно.