Muscle Tissue Lab Report

The purpose of this study was to compare contractility of individual preparations glycerinated rabbit psoas muscle exposed to two different solutions known to cause muscle contraction. A standard contracting solution without 15 mM of creatine phosphate and a second contracting solution with 15 mM of creatine phosphate were compared to one another. Creatine phosphate has been found as

Abstract: In this experiment the measurements of skeletal muscle fibers of the rabbit are in millimeters. The average length for the three muscle fibers after adding the solution A which contained only 0.25% ATP in distilled water was 20 mm. The average length for the three muscle fibers after adding the solution C which contained 0.5M KCl and 0.001M MgCl2 in distilled water was 1.77 mm and the average length for the three muscle fibers after adding the solution B which contained 0.25 % ATP and 0.5 M KCl with 0.001 M Mgcl2 in water was 1.77 mm.

The purpose of this experiment was to be able to test different intensities of warm-up conditions changes in the heart rate, skin temperature, electromyogram (EMG), and the contraction of the bicep brachii. Testing three different intensity conditions to determine which warm-up is more efficient on muscle conditioning. Bicep stretches, cardio, and aerobic stretching were the three different conditions because they focused on different muscles in the body. The warm-up that is able to efficiently deliver more oxygenated blood to the muscle is the most affective. Therefore, the predictions is that aerobic stretching will enhance muscle performance of the bicep brachii. This will happen because aerobic stretching is a high intensity warm-up that increases heart rate and cardiac output.

First, before this assignment I had no idea of the levels involved in a muscle contraction. We can directly control or regulate the activity of our skeletal muscles. Striated muscle movement, produced by the interaction of filaments containing the proteins myosin and actin, is regulated by the proteins tropomyosin and troponin on the actin filaments. When an electrical signal passes down the motor nerve to a muscle it triggers a depolarization of the muscle membrane (sarcolemma). In results, triggers the sarcoplasmic reticulum to release calcium ions into the muscle interior where they bind to troponin, which causes tropomyosin to shift the actin filament to which myosin heads need to bind to produce contraction.

Crude Extraction: Chicken muscle tissue was homogenized in a blender with cold extraction buffer in order to lyse cells, releasing LDH into

In the 10-3 pasteurized sample, the plate exhibited 71,000 cells/mL. The results of the additional dilution samples contained too few colony forming units to count. However, in the 10-7 dilution, although the plate demonstrated 12 colonies, there should have been no colony forming units on this plate. The reasons for this could have been that this sample was contaminated from “double-dipping” the sample before dispensing it onto the plate or when using the pipette, it mistakenly was inserted in a higher concentration sample and then immediately to a lower concentration sample before it was dispensed onto the plate.

47 rats were randomly allocated to one of the following groups: Sedentary (SED), rats killed one hour after last exercise (EX-1), and rats killed 24hrs after last exercise (EX-24). Rats in the SED and EX-24 groups exercised (swam) 1 hour each day, 5 days/week for 6 weeks. After each group had been killed, the subject’s soleus muscle was removed and blood samples were drawn to perform biochemical assays. Maximal GS activity was determined enzymatically in a two step process using enzyme-bound γ-glutamil phosphate as an intermediate. Using a standard curve for γ- glutamil hydroxamate over the range 50 –500μmol glutamine synthetase activity was observed and calculated as μmol product formed/min per mg protein.

The first hypothesis investigated was that as the stretch of the muscle increased, the force would increase, but at a point, it would start to decrease. This was supported by the data. The data suggests that a gastrocnemius at its resting position is not the optimal stretch for actin and myosin to have the most distance to slide past each other, and that it needs to be stretched to be able to provide the maximum amount of force. It also shows that a muscle can be stretched too far, to where the actin and myosin are slid to far, and are unable to contract fully. Past studies have shown that this is the case in frogs.

Duchenne’s Muscular Dystrophy is a recessive muscle disorder that will affect 1 in 3500 newborn boys. Early death is caused by progressive muscle wasting. The disease is caused by mutations in the dystrophin gene. Mutations in the dystrophin gene can occur, but the life span is normally longer in patients. In this journal the research was too administer injections of PRO051 for 5 weeks in 12 different patients and monitor changes in their RNA splicing and protein levels in the tibialis anterior muscle. 12 patients each performed a 6 minute walk a total of 3 different times to measure the affects that PRO051 had on the muscle fibers. The study concluded that the use of PRO051 in patients suffering from Duchenne’s Muscular Dystrophy had a modest

Skeletal muscle is the organ responsible for movements in the locomotor system. Skeletal muscle is under voluntary control, unlike smooth and cardiac muscle. Nerve impulse is the source of stimulation for the skeletal muscle activity, because skeletal muscle has no intrinsic activity because of the lack of ion channels that are responsible for the depolarization of membrane (Philip M., 2006). Muscle contraction results from the interaction of the filamentous proteins, actin and myosin. It starts when an action potential travels to the skeletal muscle along the motor neuron, where the neuromuscular junction releases acetylcholine that binds to the sarcolemme receptor, which cause Na+ to enter the muscle fiber and generate another action potential inside the muscle

Here is an explanation of the process of muscle contraction and subsequent relaxation from the point where the action potential reaches the junction between the nerve cells and the muscle-fibre. I will introduce the role of calcium, sodium and ATP, as well as taking a look at some of the proteins and enzymes utilised in this process. Action potential travels along the plasma membrane of a neuron. When the action potential reaches the synaptic end bulb it stimulates voltage-gated channels which open to allow Ca2+ to flow into the synaptic end bulb from the extra-cellular fluid, down it's electrochemical gradient. These positively charged calcium ions stimulate the synaptic vesicles into releasing acetylcholine (ACh) into the synaptic cleft

Introduction/Purpose: We are doing an experiment to stimulate person’s body to see how his nerves reacts by feeling the simulation. We need to understand the sensitivity of the areas (skin) to feel the stimulation and recognizing the objects when it touch on the skin without looking. Hypothesis: If we follow the rules step-by- step, we will gain knowledge about how quickly when touch or feeling interpreted in the cerebral cortex.

Abstract Branched-chain amino acids (BCAAs) are commonly used as a pre-workout enhancement supplement for endurance and resistance. The objective of this experiment was to explore the effects BCAAs had on muscle contraction. Muscle contractions were measured twice on each of the five subjects; once before the BCAA supplement was consumed and again twenty-minutes following the consumption of the BCAA supplement. It was hypothesized that consumption of the BCAAs would result in increased muscle contraction levels while performing a simple arm movement with a weighted object. Subjects were fit with three vinyl electrodes with electrode gel on their dominant forearms.

We used the differentiated cells C2C12 myoblast to help us determine the difference in the muscle cells. These cells are signal through the

Chemistry of Muscle Contraction Introduction Muscles, we all have them in our bodies. We use them voluntarily and involuntarily. Some people choose to emphasize their muscles’ appearance more than others but this doesn’t mean their purpose has changed. We have three different types of muscles: Cardiac Muscles, Smooth Muscles, and Skeletal Muscles.