46. The smooth sustained contraction that is a result of a high frequency of stimulation is:…
The myocardium is the middle layer and finally the endocardium is the innermost. The heart is composed of different cell types which all contribute to structural, biochemical, mechanical, and electrical properties. Forming the walls of the heart are atrial and ventricular cardiomyocytes. Cells specialize in different roles. They determine the function of a tissue in the human body. Endothelial cells form the endocardium which is the interior lining of blood vessels and cardiac valves. Over 50 percent of the cells the heart contains are cardiac fibroblasts. There are also pacemaker cells and Purkinje fibers that are specialized cardiomyocytes that generate and conduct electrical impulses. The sinoatrial node is composed of some of these pacemaker cells and rests in the right atrium generating impulses to initiate contraction of the heart. Between the atria and ventricles is the antrioventricular node. It conducts electrical impulses from the atria to the ventricles. If organs were comprised of just one type of cell they would only be able to carry out one task rather than multiple specific tasks. Instead, having multiple cells gives us an advantage. It allows our body to perform different and multiple kinds of functions. For…
• Myocadium – middle layer of heart wall, composed mainly of cardiac muscle, the layer that pumps…
images to use as references. You can use your mouse to roll over the images and click on the highlighted…
Muscular System: Anatomy Review: Skeletal Muscle Tissue 1. Fill in the characteristics of the three muscle types: Muscle Type Cardiac Skeletal Smooth Shape of cell rectangular Parallel, cylindrical banded # of nuclei multinucleated multinucleate One or two Striations striated striated non-striated Control Contraction and relaxation for the heart Provides movement and support Involuntary contraction of organ system 2. What attaches muscles to bone?…
Muscular System: The muscular systems is responsible for maintaining posture, circulating blood, and movement. Visceral muscle is found inside of organs like the stomach, intestines, and blood vessels. The stomach secretes acid and enzymes that digest food. The muscular system also has another variant which is skeletal muscle. The skeletal muscles are attached to bones and move various parts of the body. The biceps, pectoralis major, triceps, nasalis, and deltoid are five major organs in the muscular system. The biceps main job is to control the movement of the elbow and shoulder. The pectoralis major make up most of the chest bulk. The triceps help extend and retract the forearm. The nasalis compress nasal cartilage. The deltoid is responsible…
The relationship between the structure and function of the Human Cardiac Muscle cells is, in the structure, the fibers are branched together connected to the single nucleus, while the function of the tissue is to pump blood throughout the whole body.…
Cardiac muscle- The heart is a Cardiac muscle and is responsible for pumping blood around the body. The heart is made up of two parts separated by the septum. Each side has lower (Right and Left…
Human skeletal muscle consists of hundreds of individual cylindrically shaped cells (called fibers or myofibers) bound together by connective tissue. In the body, these muscles are stimulated to contract by somatic motor nerves that carry signals in the form of nerve impulses from the brain or spinal cord…
An activity that primarily utilizes type I muscle fibers is long distance running. Type I fibers are generally slow-twitch fibers, meaning they contract slowly and have a high capacity for aerobic glycolysis. Ectomorphs usually perform long distance running. In order to train slow twitch muscles (training slow twitch muscle fibers is for endurance purposes and other aerobic activities), one must increase the time under tension (TUT). Specifically, one must focus on doing higher reps (12-15) and low weights as well as doing the reps slowly with a shorter rest period than usual (possibly 30 seconds) in order to maximize and train the slow twitch muscle fibers. Slow twitch fibers are red, oxidative, contain a high content of myoglobin, utilize ATP slowly, produce a low amount of force, and have a high resistance to fatigue.…
The myocardium (cardiac muscle), is the thickest section of the heart wall and contains cardiomyocytes, the contractile cell of the heart.…
We live in our bodies. It is important that we understand how our bodies work so that we will be able to take good care of them while we are here on Earth in these spectacular containers!! Your body is covered by the largest organ and is supported within by foundation, your skeletal system.…
Cardiac muscle- found only in wall of the heart, branched cells, most are uninucleated, striated involuntary…
The outer wall of the human heart is composed of three layers. The outer layer is called the epicardium, or visceral pericardium since it is also the inner wall of the pericardium. The middle layer is called the myocardium and is composed of muscle which contracts. The inner layer is called the endocardium and is in contact with the blood that the heart pumps. Also, it merges with the inner lining (endothelium) of blood vessels and covers heart valves…
The word I chose to break down is Bradycardia. Brady which is the prefix and means slow. Cardi which is the root word and means heart. A which is the suffix and means a condition or state of. Bradycardia is a condition in which the heart rate is less than 60 beats a min. Bradycardia takes the form of sinus bradycardia, sinus arrhythmia, and second- or third-degree atrioventricular block. Sinus bradycardia may be caused by excessive vagal tone, decreased sympathetic tone, or anatomical changes. It is common in athletes and is relatively benign. It may even be beneficial in acute myocardial infarction (especially inferior). Pathological bradycardia may be symptomatic of a brain tumor, digitalis toxicity, heart block, or vagotonus. Cardiac output…