Which organ passes oxygen to the blood

The heart, blood and blood vessels work together to service the cells of the body. Using the network of arteries, veins and capillaries, blood carries carbon dioxide to the lungs for exhalation and picks up oxygen. From the small intestine, the blood gathers food nutrients and delivers them to every cell.

Blood Blood consists of: Red blood cells — to carry oxygen White blood cells — that make up part of the immune system Platelets — needed for clotting Plasma — blood cells, nutrients and wastes float in this liquid. The heart The heart pumps blood around the body.

It sits inside the chest, in front of the lungs and slightly to the left side. The heart is actually a double pump made up of four chambers, with the flow of blood going in one direction due to the presence of the heart valves. The contractions of the chambers make the sound of heartbeats. The right side of the heart The right upper chamber atrium takes in deoxygenated blood that is loaded with carbon dioxide.

The blood is squeezed down into the right lower chamber ventricle and taken by an artery to the lungs where the carbon dioxide is replaced with oxygen. The left side of the heart The oxygenated blood travels back to the heart, this time entering the left upper chamber atrium. It is pumped into the left lower chamber ventricle and then into the aorta an artery. The blood starts its journey around the body once more.

Blood vessels Blood vessels have a range of different sizes and structures, depending on their role in the body. Arteries Oxygenated blood is pumped from the heart along arteries, which are muscular.

Arteries divide like tree branches until they are slender. The largest artery is the aorta, which connects to the heart and picks up oxygenated blood from the left ventricle.

The only artery that picks up deoxygenated blood is the pulmonary artery, which runs between the heart and lungs. Capillaries The arteries eventually divide down into the smallest blood vessel, the capillary.

At the same time, a similar volume of carbon dioxide moves from the blood to the alveoli and is exhaled. During exercise, it is possible to breathe in and out more than liters about 26 gallons of air per minute and extract 3 liters a little less than 1 gallon of oxygen from this air per minute. The rate at which oxygen is used by the body is one measure of the rate of energy expended by the body.

Breathing in and out is accomplished by respiratory muscles Control of Breathing Breathing is usually automatic, controlled subconsciously by the respiratory center at the base of the brain.

Breathing continues during sleep and usually even when a person is unconscious The function of the respiratory system is to move two gases: oxygen and carbon dioxide. Gas exchange takes place in the millions of alveoli in the lungs and the capillaries that envelop them.

As shown below, inhaled oxygen moves from the alveoli to the blood in the capillaries, and carbon dioxide moves from the blood in the capillaries to the air in the alveoli. Three processes are essential for the transfer of oxygen from the outside air to the blood flowing through the lungs: ventilation, diffusion, and perfusion.

Diffusion is the spontaneous movement of gases, without the use of any energy or effort by the body, between the alveoli and the capillaries in the lungs. The body's circulation is an essential link between the atmosphere, which contains oxygen, and the cells of the body, which consume oxygen. For example, the delivery of oxygen to the muscle cells throughout the body depends not only on the lungs but also on the ability of the blood to carry oxygen and on the ability of the circulation to transport blood to muscle.

In addition, a small fraction of the blood pumped from the heart Function of the Heart The heart and blood vessels constitute the cardiovascular circulatory system. Merck and Co. From developing new therapies that treat and prevent disease to helping people in need, we are committed to improving health and well-being around the world.

The Manual was first published in as a service to the community. Your bloodstream then carries this waste gas back to the lungs where it is removed from the bloodstream and then exhaled. Your lungs and respiratory system automatically perform this vital process, called gas exchange. In addition to gas exchange, your respiratory system performs other roles important to breathing. These include:. Lung capacity declines as you age. Keep your lungs healthy by taking good care of yourself every day.

Eat a balanced diet, exercise and reduce stress to breathe easier. Get more tips for healthy lungs ». This November your donation goes even further to improve lung health and defeat lung cancer. Double Your Gift. Your tax-deductible donation funds lung disease and lung cancer research, new treatments, lung health education, and more.

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