6.4.1 Distinguish between ventilation, gas exchange and cell respiration. ventilation: the process of bringing fresh air into the alveoli and removing stale air. gas exchange: human must take in oxygen from their surrounding and release carbon dioxide, this process of swapping one gas with another is called gas exchange. cell respiration: the controlled release of energy in the form of ATP from organic compounds in cells. 6.4.2 Explain the need for a ventilation system. Diffusion of oxygen and carbon dioxide happens because there are concentration gradients of oxygen and carbon dioxide between the air and the blood.
polysaccharide polÂ·yÂ·sacÂ·chaÂ·ride (pÅl'Ä-sÄk'É-rÄ«d') or polÂ·yÂ·sacÂ·chaÂ·rid (-rÄ­d) or polÂ·yÂ·sacÂ·chaÂ·rose (-rÅs', -rÅz') n. Any of a class of carbohydrates, such as starch and cellulose, consisting of a number of monosaccharides joined by glycosidic bonds. Also called glycan.
A long chain of monosaccharides linked by glycosidic bonds is known as a polysaccharide (poly- = many). The chain may be branched or unbranched, and it may contain different types of monosaccharides. Starch, glycogen, cellulose, and chitin are primary examples of polysaccharides. Plants are able to synthesize glucose, and the excess glucose is stored as starch in different plant parts, including roots and seeds. Starch is the stored form of sugars in plants and is made up of glucose monomers that are joined by Î±1-4 or 1-6 glycosidic bonds.