MCB 450 EXAM 1 LEARNING OBJECTIVES UPDATED ACTUAL QUESTIONS AND CORRECT ANSWERS

MCB 450 EXAM 1 LEARNING OBJECTIVES UPDATED
ACTUAL QUESTIONS AND CORRECT ANSWERS

Question:
1. Know the four types of biological molecules & their general roles in Cells.
Answer:
Carbohydrates: Energy storage & structural support. Lipids: Energy storage, membrane structure &
signaling. Proteins: Enzymatic activity, structural support, transport. Nucleic Acids: Genetic information
storage & transmission.

Question:
2. Know the properties of the four types of covalent bonds (formation, enzymes, biomolecules). What is
the condensation reaction to form the covalent bonds?
Answer:
Peptide Bonds (Proteins), Glycosidic Bonds (Carbohydrates), Phosphodiester Bonds (Nucleic Acids),
Ester Bonds (Lipids). Condensation Reaction: A dehydration synthesis where water is removed to form
bonds.

Question:
3. Understand unique feature of water as a dipolar and cohesive molecule. Know the properties of
hydrogen bond.
Answer:
Water is dipolar, cohesive, has high heat capacity & solvent properties. Hydrogen bonds contribute to its
unique properties & biomolecular interactions.

Question:
4. Know the properties of hydrophilic, hydrophobic, and amphipathic Molecules.
Answer:
Hydrophilic: Water-loving (polar molecules, ions). Hydrophobic: Water-fearing (nonpolar molecules,
lipids). Amphipathic: Has both hydrophilic & hydrophobic parts (phospholids)

Question:
5. Understand the four types of weak, non-covalent interactions and their functions.
Answer:
Hydrogen Bonds, Ionic Interactions, Van der Waals Forces, Hydrophobic Interactions.

Question:
6. Learn how to solve problems involving pH.
Answer:
Use the formula pH = -log[H■]. pH increases when [H■] decreases & vice versa.

Question:
7. Understand how buffer works.
Answer:
Buffers resist pH changes by absorbing or donating H■ ions (e.g., bicarbonate buffer in blood).

, Question:
8. Know how to use Henderson-Hasselbalch equation to make or change the pH of a buffer.
Answer:
Used to calculate pH, pKa, or buffer composition.




Question:
9. Understand how the peptide bond is formed and its planar characteristics.
Answer:
Peptide bonds form via a condensation reaction. Planar due to partial double-bond character (resonance).

Question:
10. Understand major properties of each group of amino acids: their polarities, structural side chains and
characteristics.
Answer:
Nonpolar, Polar Uncharged, Acidic (negatively charged), Basic (positively charged).

Question:
11. Understand the various levels of protein structure & how they are related to one another.
Answer:
Primary (Amino Acid Sequence) Secondary (α-helices, β-sheets) Tertiary (3D folding due to side chains)
Quaternary (Multiple polypeptides interacting).

Question:
12. Why proline is called "a helix breaker"?
Answer:
Its rigid cyclic structure disrupts α-helices by introducing kinks. Has a Nitrogen - causes H bonds

Question:
13. What is a disulfide bond? How does it contribute to protein folding?
Answer:
Covalent bonds between two cysteine residues, stabilizing tertiary protein structure.

Question:
14. Know the driving forces in protein folding or stabilization of protein Conformation.
Answer:
Hydrophobic interactions, Hydrogen bonding, Ionic interactions, Van der Waals forces.

Question:
15. What's involved in protein denaturation? What do heat, pH and urea do in protein denaturation?