Exercise 5: The Length-Tension Relationship
Materials and Methods
In this experiment I used a frog anesthetized with ms222. The frog’s skin is cut and removed from both the legs, the Achilles tendon is cut and the tendon and calf muscle are removed from the lower legs. The femur muscle is also cut. Attached to the legs are femur clamps which are connected to the transducer arm, stimulation electrodes are then positioned against the muscle. I plugged the output of the transducer to the data acquisition by putting the black plug to recording input 1. Two metal stimulating electrodes are then pushed against the excised muscle. I then connected the blue plug to the negative stimulator output on the data acquisition unit and then connected the second electrode by plugging the red plug to the positive stimulator output on the unit. I then set my voltage to 2 by pressing the arrows on the control panel then set the length of the muscle by adjusting the arm on the stand frog is attached too. After achieving the right height I then shocked the frog which displayed a line on the data screen. I measured the amount of tension produced by the muscle by measuring the amplitude of the upward deflection on the line tracing. I recorded the peak of the deflection and the amplitude response which you will later see on graph 1.
1. In the sarcomere of the skeletal muscle, actin is found in? Actin is found in the thin filaments. 2. In the sarcomere of skeletal muscle, myosin is found in? Myosin is found in the thick filaments. 3. During crossbridge cycling, tension is created by? Tension is created by a change in the shape of the myosin head. 4. According to the sliding filament for skeletal muscle contraction, a shortening of the sarcomere is produced by? Shortening of the sarcomere is produced by an increase in the amount of overlap between the thick and thin filaments. 5. Maximum tension is produced in a skeletal...