Sarcomere

Use of Genetic analysis to study the nature of the Smyd1b gene in Cardiac and Skeletal Muscular Systems of Zebra Fish Prajwal Keranahalli Poolesville High School Institution: Institute of Marine and Environmental Technologies/ University of Maryland Baltimore Campus Mentor: Dr. Shaojun Du Research Project Teachers: Mr. Mark Curran, Dr. Patricia Miller Summer 2014 Abstract: One of every 5600 to 7700 males below 30 suffer from genetic muscular dystrophy. Muscular dystrophy is a group of genetic diseases

EFFECTS OF STRETCHING-MEDIATED TENSION ON VENTRICULAR CONTRACTION OF TOAD HEART INTRODUCTION Heart contraction is produced by stretching of sarcomere units, which produces strokes between myosin head and actin monomers located in the thin filament of sarcomere (Robinson, Dong et al. 2004). Changes in the resting tension of heart muscle affect the range of heart contraction. The heart has the capacity to adjust its contraction force as result of variations in ventricular filling (end-diastole), this

1) What roles did Ivan Pavlov, John B. Watson, and B. F. Skinner play in the founding of behaviorism? 125-250 words; 10pts During the early 1900’s Pavlov, Watson and Skinner played essential roles in the development of behaviorism as it is known today. These psychologists began focusing their energy on behavior rather than structuralism and functionalism. They felt that a person’s conscious thought was not important and it was the act itself that was the key to understanding essentially why people

ability to contract to structural units called sarcomeres, and a single muscle fiber can contain many thousands of these structures, aligned one next to the other. Each mature sarcomere is made up of precisely arranged and intertwined thin filaments of actin and thicker bundles of motor proteins, surrounded by other proteins. Sliding the motors along the filaments provides the force needed to contract the muscle. However, it was far from clear how sarcomeres, especially the arrays of thin-filaments, are

sliding-filament theory which explain the contraction in muscle sarcomeres (1,2). However, there are many differences in the organization of the actomyosin in CR and sarcomere. For example, F-actin in CR can organized in parallel manner and in disordered network compared to its antiparallel organization in sarcomere (3-5). In addition, the dependency of cytokinesis on myosin II has a wide variances compared to the dependency of sarcomere contraction on myosin II. For example, the current study showed

Hypertrophic cardiomyopathy, also known as the disease of the sarcomere, is a common inherited heart disease with a diverse phenotypic and genotypic expression, clinical presentation, and natural history. It is the most common genetic cardiac disease and the first to be associated with a genetic background. It is caused by more than 1,500 mutations in 11 or more genes encoding thick and thin contractile myofilament protein components of the sarcomere, or adjacent Z-disc, which are expressed almost exclusively

The theory of the sliding filament explains how the muscles contract to produce power. , actin and myosin filaments in sarcomeres of muscle fibers bind to the formation of cross-bridges and slide past each other, creating compression. This theory explains how these cross-bridges are formed and the subsequent contraction of muscle. For contraction to occur it is necessary to stimulate the muscle in the form of an impulse (action potential) from the motor neuron. one motor neuron does not stimulate

Q1 Muscle contraction can be understood as the consequence of a process of transmission of action potentials from one neuron to another. A chemical called acetylcholine is the neurotransmitter released from the presynaptic neuron. As the postsynaptic cells on the muscle cell membrane receive the acetylcholine, the channels for the cations sodium and potassium are opened. These cations produce a net depolarization of the cell membrane and this electrical signal travels along the muscle fibers. Through

lacks sarcomeres. Electron micrographs of a regions of control muscle fiber (A) and an electrocyte (B).

to the centre of the sarcomere, this is the basic concept of contraction. The myosin and actin overlap causing them to become bigger as the stretch carries on, refer to figure 4 for the contracted muscles diagram. The overlap between the myosin and actin becomes slacker and the fibres are able to elongate. Figure 4 demonstrate this exact action as the muscle becomes relaxed and elongates. When a muscle is stretched, it is extended to its maximum length: sarcomere to sarcomere, the muscle fibres will