Organic Molecules and Carbohydrates

Organic Molecules

• Organic molecules contain carbon.
• Organic molecules are abundant in living organisms.
• Macromolecules are large, complex organic molecules.

Carbon Atom

• Carbon has four electrons in its outer shell.
• Carbon needs four more electrons to fill its outer shell.
• Carbon can make up to four bonds, usually single or double bonds.
• Carbon can form nonpolar or polar bonds, with polar bonds making molecules water-soluble.

Dehydration and Hydrolysis Reactions

• Dehydration reactions link monomers to form polymers.
• Hydrolysis breaks polymers down into monomers.

Carbohydrates

• Carbohydrates consist of carbon, hydrogen, and oxygen atoms.
• Formula: Cn(H2O)n.
• Most carbon atoms in a carbohydrate are linked to a hydrogen atom and a hydroxyl group.
• Carbohydrates are polymers composed of monomer units called monosaccharides.

Monosaccharides

• Monosaccharides are the monomer units of carbohydrates.
• They are the simplest sugars.
• Most common monosaccharides have 5 or 6 carbons.

Disaccharides

• Disaccharides are composed of two monosaccharides.
• They are joined by a dehydration or condensation reaction, forming a glycosidic bond.
• Disaccharides are broken apart by hydrolysis.
• Examples include sucrose, maltose, and lactose.

Polysaccharides

• Polysaccharides are long polymers formed by linking many monosaccharides.