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Excersice 02-01

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Excersice 02-01
Exercise 2: Skeletal Muscle Physiology: Activity 1: The Muscle Twitch and the Latent Period Lab Report Pre-lab Quiz Results You scored 100% by answering 5 out of 5 questions correctly. 1. Skeletal muscles are connected to bones by You correctly answered: b. tendons. 2. Skeletal muscles are composed of hundreds to thousands of individual cells called You correctly answered: c. fibers. 3. The term motor unit refers to You correctly answered: c. one motor neuron and all of the skeletal muscle fibers it innervates. 4. The motor neuron and muscle fiber intersect at what is called You correctly answered: d. the neuromuscular junction. 5. A twitch is You correctly answered: a. one contractile response to a single action potential.

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Experiment Results Predict Question: Predict Question: Will changes to the stimulus voltage alter the duration of the latent period? Your answer : a. Yes, changing the stimulus voltage will change the latent period duration proportionately. Stop & Think Questions: What is the period of time that elapses between the generation of an action potential and the start of muscle tension development in a muscle fiber? You correctly answered: c. the latent period What occurs during the latent period of these isometric contractions? You correctly answered: b. All the steps of excitation-contraction coupling occur. Experiment Data: Voltage 0.0 3.0 4.0 6.0 8.0 10.0 Length 75 75 75 75 75 75 Active Force 0.00 1.04 1.32 1.65 1.81 1.82 Passive Force 0.00 0.00 0.00 0.00 0.00 0.00 Total Force 0.00 1.04 1.32 1.65 1.81 1.82 Latent Period ----3.20 2.80 2.40 2.80

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Post-lab Quiz Results You scored 85% by answering 6 out of 7 questions correctly. 1. An action potential in a motor neuron triggers the release of which neurotransmitter? You correctly answered: b. acetylcholine 2. The term skeletal muscle fiber refers to You correctly answered: a. an individual skeletal

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