Cariovascular System
Running Head: CARIOVASCULAR SYSTEM
Cardiovascular System
BSC1011 Advanced Biology
Tuesday, January 17, 2012
Cardiovascular System
The heart weighs 300 grams and is shaped like a grapefruit and has two atria, two ventricles, and four valves receive blood from both venae cavae and the four pulmonary veins, and throw it into the aorta and pulmonary trunk. The heart pumps blood to 9 liters per day, making from 60 to 160 beats per minute. The heart is covered with a dense fibrous membrane - the pericardium, forming serous cavity filled with liquid, which prevents friction when it decreases. The heart consists of two pairs of chambers - the atria and ventricles, which act as separate pumps. The right half of the heart "pumps" venous-rich carbon dioxide blood through the lungs, it is - a small circulation. The left half throws oxygenated blood that is passed from the lungs into the systemic circulation. Venous blood from the upper and lower hollow vein enters the right atrium which consist of the “superior vena cava” which is a smaller vein that circulates de-oxygenated blood from the upper half of the body to the right atrium and the “inferior vena cava” which is a larger vein that circulates de-oxygenated blood from the lower half of the body to the right atrium. Four pulmonary veins deliver arterial blood to the left atrium.
Atrioventricular valves are of special thin papillary muscles and tendinous filaments attached to the ends of the sharp edges of valves. These structures are fixed valves and prevent them from "falling through" (prolapse) back into the atrium during ventricular systole. The left ventricle is formed by thick muscle fibers than the right ventricle because it is opposed to higher pressure of blood in the systemic circulation and should make greater efforts to overcome it during systole. “Located on the right dorsal side of the heart is the “tricuspid valve” also known as the right atrioventricular
Cardiovascular System
BSC1011 Advanced Biology
Tuesday, January 17, 2012
Cardiovascular System
The heart weighs 300 grams and is shaped like a grapefruit and has two atria, two ventricles, and four valves receive blood from both venae cavae and the four pulmonary veins, and throw it into the aorta and pulmonary trunk. The heart pumps blood to 9 liters per day, making from 60 to 160 beats per minute. The heart is covered with a dense fibrous membrane - the pericardium, forming serous cavity filled with liquid, which prevents friction when it decreases. The heart consists of two pairs of chambers - the atria and ventricles, which act as separate pumps. The right half of the heart "pumps" venous-rich carbon dioxide blood through the lungs, it is - a small circulation. The left half throws oxygenated blood that is passed from the lungs into the systemic circulation. Venous blood from the upper and lower hollow vein enters the right atrium which consist of the “superior vena cava” which is a smaller vein that circulates de-oxygenated blood from the upper half of the body to the right atrium and the “inferior vena cava” which is a larger vein that circulates de-oxygenated blood from the lower half of the body to the right atrium. Four pulmonary veins deliver arterial blood to the left atrium.
Atrioventricular valves are of special thin papillary muscles and tendinous filaments attached to the ends of the sharp edges of valves. These structures are fixed valves and prevent them from "falling through" (prolapse) back into the atrium during ventricular systole. The left ventricle is formed by thick muscle fibers than the right ventricle because it is opposed to higher pressure of blood in the systemic circulation and should make greater efforts to overcome it during systole. “Located on the right dorsal side of the heart is the “tricuspid valve” also known as the right atrioventricular
References: Aronson, P. & Ward, J. (2007), “The Cardiovascular System at a Glance”, Wiley-Blackwell, 3rd Edition Levick, R. (2010), “An Introduction to Cardiovascular Physiology”, Hodder Arnold Publisher, 5th Edition Sutton, A. (2010), “Cardiovascular Disorders Book (Health Reference Series)”, Omnigraphics Inc. Watchie, J. (2009), “Cardiovascular and Pulmonary Physical Therapy: A Clinical Manual”, Saunders, 2nd Edition