Biomolecules
Supplemental Instruction
Iowa State University / Leader: / Chelsea
Course: / Bio 212(2)
Instructor: / Vleck
Date: / 8/28/12

Vocabulary:

  • Monomer-One molecule
  • Polymer-Multiple monomers linked together.
  • Saturated bond- Made of Single bonds.
  • Unsaturated bond- Made of Double bonds.
  • Macromolecule-A large polymer such as carbohydrates, proteins, etc.
  • Hydrogenation-The use of hydrogen to convert double bonds to single bonds or cis bonds to trans bonds.
  • Amphipathic- Having both a polar and a nonpolar group.
  • Functional Groups- A group that has significance and is not the backbone of the molecule. Examples- OH, COOH, NH3, etc.
  • Isomers- Two molecules that have the same chemical formula but have different structures.
  • Enantiomer/Chirality- Mirror image/Has four different groups on the alpha-carbon.
  • Polar/Nonpolar-Based on equal/unequal sharing of the alpha atom, which comes from the electronegativity differences.
  • Hydrophilic/Hydrophobic- Water loving/water hating.

Protein Structure:

  • Primary:
    Chain of amino acids linked together.
  • Secondary:
    Folding that occurs between the primary strand that creates alpha helices and beta sheets.
  • Tertiary:
    Secondary structures fold into a three dimensional shape.
  • Quaternary:

Two or more polypeptides bind together to form a protein.

What determines the function of a protein?

The amino acid sequence.

Protein Functions:

Catalyst- speeds up reactions

Structural-collagen, tubulin, etc.

Transport-Hemoglobin

Hormones-Insulin

Defense-Antibodies

Movement-Actin and myosin

Polysaccharide Functions:

Energy and Carbon storage- Starch and glycogen

Structural-Cellulose and Chitin

Why is Cellulose indigestible in most animals?

Because it contains a 1-4 linkage between the two molecules that is in the beta position, meaning its pointing up rather than down.

Lipid Functions:

Barriers

Energy stores/storage

Messenger

What makes lipids hydrophobic?

Having few or no polar groups (remember that phospholipids are the except to this rule because they have a polar head with nonpolar tails)

Draw a picture of steroids and phospholipids. Which of these forms bilayers?

Phospholipids because of their amphipathic nature (having both polar and nonpolar ends) allows the tails to turn inwards and the heads to turn outwards to create a barrier.

Where are bilayers found in the body? How are they useful?

In the cells. They can be used for many things, but many they act as a barrier, which can also allow selective transport of certain molecules across. They can also be used to transport molecules when they form a micelle.

Draw a cis and trans unsaturated fatty acid. How does being unsaturated change the state the lipid is in at room temperature?

Saturated is a solid at room temperature, but unsaturated molecules are liquid at room temp.

List the four parts of an amino acid (i.e. What four parts are connected to the α carbon?). How many amino acids are considered to be common in the body?

Amino group, Carboxyl group, Hydrogen and an R group make up the general amino acid. There are twenty different amino acids in the body and they are all different based on the differences we see in the R groups.

What part of an amino acid makes it hydrophobic or hydrophilic? Polar/non-polar/acidic/basic?

The R group decides whether any of these differences are present.

Fill in (Not all blanks will be filled in):

Macromolecule / Carbohydrates / Proteins / Lipids
Common Name / Sugars / - / Fats
Polymer / Simple sugars / Amino Acids / Phospholipids
Monomer / Multiple sugars / AA’s chain / Multiple Phospholipids
Formula / Cn(H2O)n / AA’s / (CH2)n
Other Important
Info / Take ring form in water. / Each protein is different based on sequence. / Mostly hydrophobic and insoluble.