Search results
Results from the WOW.Com Content Network
The heart pumps blood to all parts of the body providing nutrients and oxygen to every cell, and removing waste products. The left heart pumps oxygenated blood returned from the lungs to the rest of the body in the systemic circulation. The right heart pumps deoxygenated blood to the lungs in the pulmonary circulation.
Oxygen therapy may be used to assist in raising blood oxygen levels. Oxygenation occurs when oxygen molecules (O 2) enter the tissues of the body. For example, blood is oxygenated in the lungs, where oxygen molecules travel from the air and into the blood. Oxygenation is commonly used to refer to medical oxygen saturation.
Coronary arteries supply oxygenated blood to the heart muscle. Cardiac veins then drain away the blood after it has been deoxygenated. Because the rest of the body, and most especially the brain , needs a steady supply of oxygenated blood that is free of all but the slightest interruptions, the heart is required to function continuously.
The heart did not pump blood around, the heart's motion sucked blood in during diastole and the blood moved by the pulsation of the arteries themselves. [93] Galen believed the arterial blood was created by venous blood passing from the left ventricle to the right through 'pores' between the ventricles. [90]
Blood flow may increase up to twice the normal flow but no more. If the increased blood flow is sufficient to supply the brain's oxygen needs then no symptoms will result. [6] However, if blood flow cannot be increased or if doubled blood flow does not correct the problem, symptoms of cerebral hypoxia will begin to appear.
Blood is a body fluid in the circulatory system of humans and other vertebrates that delivers necessary substances such as nutrients and oxygen to the cells, and transports metabolic waste products away from those same cells. [1] Blood is composed of blood cells suspended in blood plasma.
The period of time that begins with contraction of the atria and ends with ventricular relaxation is known as the cardiac cycle. The period of contraction that the heart undergoes while it pumps blood into circulation is called systole. The period of relaxation that occurs as the chambers fill with blood is called diastole.
Coronary occlusion is caused by plaque inside of the blood vessels that direct oxygen rich blood to the heart. [8] Plaque is caused by fatty deposits and scar tissue that cling to the walls of coronary arteries. [9] The development of plaque takes years and leads to stenosis of the coronary arteries and progressively reduces blood flow. [8]