Muscle Contraction Lab Report

Words: 527
Pages: 3
Open Document
Muscle contractions are an essential part of carrying out our daily lives. They allow us to hold this lab report and turn the pages, as well as, move our eyes across this paper. In order to fully understand a skeletal muscle contraction, one must take a look at the anatomy and physiology on a cellular level. Each muscle is organized into a bundle of muscles fibers along with blood vessels and nerves, which help to send the signals to contract. Within each muscle fiber are myofibrils, which are the basic muscle cells that contain the contractile units, called sarcomeres. The chains of sarcomeres found in each myofibril are what give vertebrates muscles their striated appearance. The sliding filament mechanism between the thick and thin filaments …show more content…
This process is driven by a physical interaction between myosin heads and adjacent actin filaments, which is governed by the regulatory proteins troponin and tropomyosin. Troponin is a Ca++ binding protein that allows myosin to bind by controlling the shape of tropomyosin, which is part of the thin filament actin. When action potentials have been sent from the central nervous system to the effector neurons, muscles receive the signals through T-tubules of the sarcolemma which then triggers release of Ca++. The Ca++ ions then bind to troponin which moves tropomyosin from its blocking position and allows myosin to bind to actin (Johnsen, p. 38). Subsequent binding and hydrolysis of ATP to the myosin head helps to produce the conformational change to the myosin head in order to produce the power strokes that move actin filaments.
In this lab exercise, we studied the responses of many muscle fibers with their motor neurons attached, specifically, a frog gastrocnemius. The property of excitable tissue is defined by the all-or-nothing law where the nature of the response does not depend on the strength of the stimulus, as long as the strength reached threshold. What we were interested in studying however, was how the strength of the muscle response (or tension developed) can be
Show More

Related Documents: Muscle Contraction Lab Report

Essay about PEX 02 02

Name: Exercise 2: Skeletal Muscle Physiology: Activity 2: The Effect of Stimulus Voltage on Skeletal Muscle Contraction Lab Report Pre-lab Quiz Results You scored 100% by answering 4 out of 4 questions correctly. 1. Skeletal muscle fibers are innervated (stimulated) by You correctly answered: c. motor neurons. 2. A single action potential propagating down a motor axon results in You correctly answered: d. a single action potential and a single contractile event in the muscle fibers it innervates. 3…

Words 671 - Pages 3

Physiology: Neuromuscular Junction and Skeletal Muscle Fiber Essay

Exercise 2: Skeletal Muscle Physiology: Activity 1: The Muscle Twitch and the Latent Period Lab Report Pre-lab Quiz Results You scored 40% by answering 2 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 Your answer : d. myofilaments. Correct answer: c. fibers. 3. The term motor unit refers to Your answer : a. all of the motor neurons that innervate one…

Words 957 - Pages 4

Essay on Histology Lab

Histology Laszlo Vass, Ed.D. Version 42-0013-00-01 Lab RepoRt assistant This document is not meant to be a substitute for a formal laboratory report. The Lab Report Assistant is simply a summary of the experiment’s questions, diagrams if needed, and data tables that should be addressed in a formal lab report. The intent is to facilitate students’ writing of lab reports by providing this information in an editable file…

Words 1351 - Pages 6

Athlete's Heart Vs Sedentary Heart

(the difference in the volume of blood in the ventricle before and after contraction) is known as stroke volume. Cardiac output is the volume of blood ejected from the ventricles in a minute. Cardiac output is the response for meeting the demand of oxygen in the body. As an athlete begins to train their breathing rate increases therefore increasing their consumption of oxygen as there is a higher demand by the working muscles. Stroke volume is determined by the hearts ability to fill and empty in…

Words 1275 - Pages 6

A&P I notes Essay

systems Functions: Directs long-term changes in activities of other organ systems; adjusts metabolic activity and energy used by the body; controls many structural and functional changes during development 5. Muscular System Major Organs: skeletal muscles and associated tendons and aponeuroses (tendous sheets) Functions: provides movement; provides protection and support for other tissues; generates that maintains body temperature 6. The Cardiovascular System Major Organs: heart, blood, blood…

Words 1935 - Pages 8

Obstetric Medications Essay

Southeastern Louisiana University College of Nursing & Health Sciences School of Nursing Nursing Lab 473 MEDICATION FORM Medication Name/Dose Medication Classification Mechanism of Action Why is your pt. receiving the med? Common Side Effects Drug Interactions PRIORITY Nursing Implications/Concerns and Pertinent Labs Brand: Benadryl Generic: Diphenhydramine Antihistamine, H1, Sedating An ethanolamine that competitively blocks the effects of histamine at peripheral H1 receptor sites Produces anticholinergic…

Words 4845 - Pages 20

Essay about Actions of Drugs

Actions of drugs on cardiovascular preparations Introducion The experiment outlined in this report was carried out with the intention to observe and explore the effects of certain named drugs on a vascular preparation, in the cardiac region specifically. The cardiovascular preparation used in this experiment was an isolation of the descending aorta of a rat. This isolate is particularly useful as it mirrors the responses that would be observed in a human sample, thus this experiment will give…

Words 2075 - Pages 9

Reflex and Special Senses Essay

Lab Report: Reflex and Special Senses Please fill out this report and submit it to the dropbox. Do not hand in your own form. It will not be graded and you will receive a zero for the lab. You must get all parts correct to get credit for the question * Please note that although you do not hand in items in observations, it is very important to do these as you may see some of these items on future/associated lab quizzes or be asked about some of these…

Words 2718 - Pages 11

Reflex and Pic Essay

Admission to the Labor and Delivery Unit At 0630 the nurse calls to report to the healthcare provider, who prescribes the following: admit to labor and delivery, bedrest with bathroom privileges (BRP), IV D5LR at 125 ml/hr, CBC with platelets, clotting studies, liver enzymes, chemistry panel, 24-hour urine collection for protein and uric acid, ice chips only by mouth, nonstress test, hourly vital signs, and DTRs. 5. While awaiting the lab results, which nursing intervention has the highest priority…

Words 1477 - Pages 6

Physio 9.0 Cardio Lab Report Essay

Physio Cardio Lab Report Answers Activity 1 Questions: 1. Explain how the body establishes a pressure gradient for fluid flow. Pressure gradient is the flow rate of a liquid through a pipe. This is directly proportional to the difference between the pressures at the two ends of the pipe and inversely proportional to the pip's resistance. The pressure gradient is directly dependent upon blood vessel radius which essentially controls blood flow. The bigger the blood vessel radius, the more…

Words 2293 - Pages 10