Chapter 4: Introduction to organic Chemistry

Allied Health Biochemistry - Multiple Choice Exam

Section 1: Organic Molecules & Carbon Chemistry

1. Which of the following elements is the backbone of organic molecules?
   a) Hydrogen
   b) Oxygen
   c) Carbon
   d) Nitrogen
   Answer: c) Carbon

2. What makes carbon ideal for forming complex organic molecules?
   a) It forms ionic bonds
   b) It forms up to four covalent bonds
   c) It can only bond with hydrogen
   d) It is highly electronegative
   Answer: b) It forms up to four covalent bonds

Section 2: Carbon Skeletons & Functional Groups

3. Which of the following best describes a carbon skeleton?
   a) A single oxygen atom attached to carbon
   b) A nitrogenous base connected to a sugar
   c) A backbone of carbon atoms forming chains or rings
   d) A molecule composed entirely of nitrogen
   Answer: c) A backbone of carbon atoms forming chains or rings

4. Which of these functional groups is acidic?
   a) Amino (-NH₂)
   b) Hydroxyl (-OH)
   c) Carboxyl (-COOH)
   d) Sulfhydryl (-SH)
   Answer: c) Carboxyl (-COOH)

Section 3: Hydrocarbons & Isomerism

5. Which of the following hydrocarbons contains a triple bond?
   a) Alkane
   b) Alkene
   c) Alkyne
   d) Aromatic hydrocarbon
   Answer: c) Alkyne

6. What is an isomer?
   a) A compound with a different molecular formula but the same structure
   b) A compound with the same molecular formula but different structures
   c) A hydrocarbon with only single bonds
   d) A lipid molecule with a phosphate group
   Answer: b) A compound with the same molecular formula but different structures

7. Which type of isomer has the same connectivity of atoms but differs in spatial arrangement?
   a) Structural isomer
   b) Geometric isomer
   c) Enantiomer
   d) Cis-trans isomer
   Answer: b) Geometric isomer

Section 4: Carboxylic Acids, Esters, and Amines

8. Which functional group is found in carboxylic acids?
   a) -NH₂
   b) -COOH
   c) -OH
   d) -SH
   Answer: b) -COOH

9. Which functional group is characteristic of esters?
   a) -COOH
   b) -NH₂
   c) -COO-
   d) -OH
   Answer: c) -COO-

10. Amines contain which functional group?
    a) -OH
    b) -COOH
    c) -NH₂
    d) -SH
    Answer: c) -NH₂

Section 5: Sulfhydryl & Phosphate Groups

11. Which of the following functional groups is involved in forming disulfide bonds in proteins?
    a) Hydroxyl (-OH)
    b) Sulfhydryl (-SH)
    c) Amino (-NH₂)
    d) Phosphate (-PO₄³⁻)
    Answer: b) Sulfhydryl (-SH)

12. Which functional group is involved in ATP and energy transfer?
    a) Carboxyl (-COOH)
    b) Amino (-NH₂)
    c) Phosphate (-PO₄³⁻)
    d) Hydroxyl (-OH)
    Answer: c) Phosphate (-PO₄³⁻)

Section 6: Biomolecules – Carbohydrates, Proteins, Nucleic Acids, Lipids

13. What is the monomer of carbohydrates?
    a) Amino acid
    b) Monosaccharide
    c) Nucleotide
    d) Fatty acid
    Answer: b) Monosaccharide

14. Which macromolecule contains genetic information?
    a) Proteins
    b) Nucleic acids
    c) Carbohydrates
    d) Lipids
    Answer: b) Nucleic acids

15. Which type of lipid is used for long-term energy storage?
    a) Phospholipids
    b) Steroids
    c) Triglycerides
    d) Nucleotides
    Answer: c) Triglycerides

16. Which lipid is a major component of cell membranes?
    a) Phospholipids
    b) Triglycerides
    c) Steroids
    d) Cholesterol
    Answer: a) Phospholipids

17. What type of lipid serves as a precursor for steroid hormones?
    a) Triglycerides
    b) Phospholipids
    c) Cholesterol
    d) Glycolipids
    Answer: c) Cholesterol

Section 7: The Glycemic Index & Metabolism

18. The glycemic index measures:
    a) How quickly a carbohydrate raises blood sugar
    b) The fiber content of food
    c) The protein content of food
    d) The fat percentage in food
    Answer: a) How quickly a carbohydrate raises blood sugar

19. Which macromolecule is digested first for energy in the human body?
    a) Lipids
    b) Proteins
    c) Carbohydrates
    d) Nucleic acids
    Answer: c) Carbohydrates

20. Which type of fat is considered the healthiest for heart health?
    a) Saturated fats
    b) Trans fats
    c) Unsaturated fats
    d) Hydrogenated oils
    Answer: c) Unsaturated fats