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Carbohydrates
Carbohydrates can be broken down into three categories based on the number of sugars.
1 sugar present is called a monosaccharide. The three main types of monosaccharides are glucose,
fructose, and galactose.
2 sugars present is called a disaccharide. The three main types of disaccharides are sucrose (glucose +
fructose), lactose (glucose + galactose) and maltose (glucose + glucose).
Multiple sugars connected is called a polysaccharide. List the 4 main types of polysaccharides and their
functions:
starch (energy storage in plant cells)
glycogen (energy storage in animal cells)
cellulose (major component in cell walls)
chitin (major component in fungus cell walls and exoskeletons of insects).
The link that joins sugar molecules together is called a glycosidic linkage. When two molecules are
joined together, it is called condensation or dehydration reaction because a water molecule is lost.
Draw a rough sketch of what a polysaccharide would look like.
Lipids
Lipids can be broken down into 4 categories
1. Triglycerides are fats and oils. They contain 3 fatty acid chains attached to a glycerol molecule.
They can be saturated, monounsaturated, and poly unsaturated. Saturated fats do not have a
double bond, are solids at room temperature, and typically come from animals. An example is
butter. Unsaturated fats do have double bonds, are liquids at room temperature, and typically
come from plants. An example is vegetable oil. Draw the difference between a saturated and
unsaturated fat.
2. Phospholipids consist of 2 fatty acid chains and 1 phosphate group attached to a glycerol
molecule. It has a polar and a nonpolar region making it amphipathic. Phospholipids make up
our cell membranes. Draw what a phospholipid looks like.
3. Steroids are 4 linked carbon rings. They consist of cholesterol and certain hormones. Draw
what a steroid looks like.
4. Waxes are used for protection.
Proteins
Proteins have a variety of functions. Some functions include structural, storage, transport,
defensive, signaling, and enzymes.
Proteins are made up of monomers called amino acids and through peptide bonds create
polymers called polypeptides.
There are 4 levels of protein structure. For each level, write a brief description and draw a rough
sketch of what that level of structure looks like.
Primary  order of amino acids
Secondary  basic 3D shape that results from hydrogen bonding interactions on the ends of the
polypeptide chain. Can be alpha helix or beta sheet. Proteins whose shape are dominated by this
interaction are called fibrous.
Tertiary  more advanced 3D shape that results from interactions of other amino acids besides the
ends. Includes hydrogen bonding, ionic bonding, hydrophobic effect, and disulfide bonds.
Quaternary  a protein where multiple polypeptides join together. A classic example is
hemoglobin.
Nucleic Acids
The two main types of nucleic acids are DNA and RNA. They are each polymers made up from the
monomer of a nucleotide. A nucleotide consists of 3 parts: nitrogen base, a five carbon sugar, and a
phosphate group. There are 5 types of bases. The purines are two ring structures and include adenine
and guanine. The pyrimidines are one ring structures and include uracil, thymine, and cytosine. Draw
the difference between a purine and pyrimidine below. Be sure to include all parts of the nucleotide.
The 3 ways in which DNA/RNA differ is that
1. Sugar in RNA is ribose, in DNA it is deoxyribose
2. Thymine in RNA is replaced by uracil
3. RNA is normally single stranded while DNA is usually in a double helix.
Draw a DNA molecule vs. an RNA molecule, ensuring to highlight these differences.