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Organic Chemistry. How are Polymers Formed?. Within cells, small organic molecules are joined together to form larger molecules to form macromolecules . Long molecules are called polymers , which are built from repeating units, monomers , linked together.
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How are Polymers Formed? • Within cells, small organic molecules are joined together to form larger molecules to form macromolecules. • Long molecules are called polymers, which are built from repeating units, monomers, linked together
Monomers are connected by covalent bonds, which form through the loss of water molecule. This chemical reaction is called a condensation reaction or dehydration synthesis • When two monomers form a bond, one monomer provides a hydroxyl group (OH) and the other monomer a hydrogen (H) • Dehydration synthesis requires energy investment from the cell and the involvement of enzymes
When does dehydration synthesis occur? • Whenever molecules need to be made: • Building proteins to make muscle • Plants producing sucrose or starch from glucose produced in photosynthesis • Producing antibodies to fight off disease
How are Polymers broken down? • Polymers are broken down to monomers by hydrolysis. A chemical reaction that splits molecules apart by the addition of water; enzymes are involved
When does hydrolysis occur? • Digestion – during digestion of food, organic polymers are too large for absorption by cells. Various enzymes aid hydrolysis to produce monomers, which are small enough to be absorbed by cells lining the gut and transported to the blood stream for distribution to other cells of the body • Plants also need to digest stored polymers to provide energy for life processes