Search results
Results from the WOW.Com Content Network
Cerebral blood flow (CBF) is the blood supply to the brain in a given period of time. [8] In an adult, CBF is typically 750 millilitres per minute or 15.8 ± 5.7% of the cardiac output. [9] This equates to an average perfusion of 50 to 54 millilitres of blood per 100 grams of brain tissue per minute. [10] [11] [12]
Diagram of the arterial circulation at the base of the brain (inferior view), the circle of Willis is drawn in the upper half. Blood flows up to the brain through the vertebral arteries and through the internal carotid arteries.
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 ]
Diagram of the human heart showing blood oxygenation to the pulmonary and systemic circulation. 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.
Collateral circulation is the alternate circulation around a blocked artery or vein via another path, such as nearby minor vessels. [1] It may occur via preexisting vascular redundancy (analogous to engineered redundancy), as in the circle of Willis in the brain, or it may occur via new branches formed between adjacent blood vessels (neovascularization), as in the eye after a retinal embolism ...
The heart is a muscular organ situated in the mediastinum.It consists of four chambers, four valves, two main arteries (the coronary arteries), and the conduction system. The left and right sides of the heart have different functions: the right side receives de-oxygenated blood through the superior and inferior venae cavae and pumps blood to the lungs through the pulmonary artery, and the left ...
the vagus nerve, part of the parasympathetic branch of the autonomic nervous system, to lower heart rate. The cardiovascular centre also increases the stroke volume of the heart (that is, the amount of blood it pumps). These two changes help to regulate the cardiac output, so that a sufficient amount of blood reaches tissues.
Blood flow diagram of the human heart. Blue components indicate de-oxygenated blood pathways and red components indicate oxygenated pathways. The heart functions as a pump and acts as a double pump in the cardiovascular system to provide a continuous circulation of blood throughout the body.