Macromolecules

• Macromolecules are large molecules made of smaller molecules joined together.

• the four classes of macromolecules are: carbohydrates, lipids, proteins, and nucleic acids.

• Monomers are the building blocks of polymers.

• Monomers are subunits.

• The monomers of carbohydrates are monosaccharides, and its polymers are polysaccharides.

• The monomers of lipids are glycerol and fatty acids, and its polymers are fats.

• The monomers of proteins are amino acids, and its polymers are polypeptides.

• The monomers of nucleic acids are nucleotides, and its polymers are DNA and RNA.

Hydrolysis and Dehydration Reactions

• Dehydration (synthesis) reactions joins monomers together by a covalent bond and water is released.

• Hydrolysis (degradation) reactions take place when water molecules are added to break a covalent bond.

• (“Hydro” means water and “lysis” means breaking/rupturing.)

Synthesis and Degradation

• Enzymes are required for cells to carry out reactions.

• Enzymes are a molecule that speed up a chemical reaction.

• They are not consumed or changed in the reaction.

Carbohydrates

• Carbohydrates are found in grains, fruits, and veggies.

• They provide energy to the body in the form of glucose, and they provide cell structure.

• The three main types of carbohydrates are: monosaccharides (one), disaccharides (two), and polysaccharides (many).

• Carbohydrates have the molecular formula CH20.

• There are two hydrogens for each single carbon and oxygen.

• Carbohydrates contain a carbonyl group (C=O), hydroxyl groups (O-H), and many carbon-hydrogen bonds (C-H).

• Carbohydrates are hydrophilic (they love water).

What Distinguishes One Monosaccharide from Another?

• Monosaccharide monomers are simple sugars that structurally vary in four primary ways.

• The first way that they structurally vary is in the number of carbons present. If there are three carbons present, it would be known as a “triose,” if there are five carbons present, then it would be a “pentose,” if there are six carbons, then it would be a “hexose.”

• The second way they vary is the arrangement of functional groups.

• The third way they vary is by linear and alternate ring forms.

Three Structural Isomers of a Hexose Monosaccharide

• The structural isomers/formula is: C6H12O6.

1. Glucose is an important source of energy.

2. Galactose is part of lactose/milk sugar.

3. Fructose is part of sucrose/fruit.