At the venous end of a capillary, osmotic pressure is higher than blood pressure; therefore, water tends to enter the bloodstream. Water and other small molecules can cross through the cells of a capillary wall or through tiny clefts that occur between the cells.
http://encyclopedia.lubopitko-bg.com/Capillary_Exchange.html
1 At the middle of the capillary bed, blood pressure in the vessel equals the osmotic pressure of the blood in the vessel. 2  The net result is that fluid passes equally between the capillary vessel and the body tissue. 3  Gasses, nutrients, and wastes are also exchanged at this point.
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Gas Exchange Between Alveolar Spaces and Capillaries. The function of the respiratory system is to exchange two gases: oxygen and carbon dioxide. The 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.
http://www.merckmanuals.com/home/lung-and-airway-disorders/biology-of-the-lungs-and-airways/exchanging-oxygen-and-carbon-dioxide
Tissue fluid is simply the fluid that surrounds the cells of the body. In other words, substances that leave a capillary pass through tissue fluid before entering the body’s cells, and substances that leave the body’s cells pass through tissue fluid before entering a capillary.
http://encyclopedia.lubopitko-bg.com/Capillary_Exchange.html
The pumping of the heart sends blood by way of arteries to the capillaries where exchange takes place across thin capillary walls (Fig. 11.6) . Blood that has passed through the capillaries returns to the heart via veins. Capillary walls are largely composed of one layer of epithelial cells connected by tight junctions.
http://encyclopedia.lubopitko-bg.com/Capillary_Exchange.html
Capillaries are where fluids, gasses, nutrients, and wastes are exchanged between the blood and body tissues by diffusion. Capillary walls contain small pores that allow certain substances to pass into and out of the blood vessel.
http://biology.about.com/od/anatomy/ss/capillary.htm
Capillaries measure in size from about 5-10 microns in diameter. Capillary walls are thin and are composed of endothelium (a type of simple squamous epithelial tissue). Oxygen, carbon dioxide, nutrients and wastes are exchanged through the thin walls of the capillaries.
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Ventilation is the process by which air moves in and out of the lungs. Diffusion is the spontaneous movement of gases, without the use of any energy or effort by the body, between the gas in the alveoli and the blood in the capillaries in the lungs. Perfusion is the process by which the cardiovascular system pumps blood throughout the lungs.
http://www.merckmanuals.com/home/lung-and-airway-disorders/biology-of-the-lungs-and-airways/exchanging-oxygen-and-carbon-dioxide
A capillary is an extremely small blood vessel located within the tissues of the body, that transports blood from arteries to veins. Capillaries are most abundant in tissues and organs that are metabolically active.
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The flow of blood in the capillaries is controlled by structures called precapillary sphincters. These structures are located between arterioles and capillaries and contain muscle fibers that allow them to contract. When the sphincters are open, blood flows freely to the capillary beds of body tissue.
http://biology.about.com/od/anatomy/ss/capillary.htm
what is the exchange of gases between capillaries and body tissue cells?
The respiratory system is the exchange of gases between capillaries and body tissue cells. The exchange of gases between capillaries and body tissue cells is the respiratory system.