Introduction to Biochemistry & Biomolecules

Learning Objectives

By the end of this week, you should be able to:

1. Define biochemistry and explain its role in health sciences.

2. Identify and describe the four major classes of biomolecules: carbohydrates, proteins, lipids, and nucleic acids.

3. Understand basic chemical bonds (covalent, hydrogen, ionic) and how they contribute to molecular structure.

4. Begin connecting molecular structures with their functions in biological systems.

Definition:

Biochemistry is the branch of science that explores the chemical processes within and related to living organisms. It combines biology and chemistry to understand cellular mechanisms.

Importance:

It provides insights into how biomolecules support life, how metabolic pathways function, and how disruptions in these processes can lead to diseases.

The Four Major Biomolecules

1. Carbohydrates

   1. Function: Energy source and structural support.

   2. Examples:

      1. Glucose (energy),

      2. starch (energy storage in plants),

      3. glycogen (energy storage in animals),

      4. cellulose (structural component in plants).

2. Proteins

   1. Function: Catalysis (enzymes), structure, transport, signaling, and immune responses.

   2. Examples: Enzymes, antibodies, hemoglobin.

3. Lipids

   1. Function:

      1. Energy storage,

      2. cellular membrane structure,

      3. signaling molecules.

   2. Examples:

      1. Triglycerides,

      2. phospholipids,

      3. cholesterol.

4. Nucleic Acids

   1. Function: Storage and transmission of genetic information.

   2. Examples:

      1. DNA (genetic blueprint)

      2. RNA (protein synthesis)

5. Basic Chemical Bonds

   1. Covalent Bonds:

      1. Strong bonds formed by the sharing of electron pairs between atoms.

      2. Example: The bonds between carbon atoms in glucose.

6. Hydrogen Bonds:

   1. : Weaker bonds important in determining the structure of water and biological molecules (e.g., secondary structure of proteins).

7. Ionic Bonds:

   1. Description: Bonds formed by the attraction between oppositely charged ions.

   2. Example: Salt (NaCl) formation.

3. Practice Questions

Level 1 (Basic Recall)

1. Definition & Importance:

• Define biochemistry. Why is it important in healthcare and medicine?

2. Biomolecule Identification:

• List the four major classes of biomolecules and one key function for each.

3. Bond Types:

• What type of bond links amino acids in a protein?

Level 2 (Application & Analysis)

4. Energy Storage Comparison:

• Explain why lipids are more efficient for long-term energy storage compared to carbohydrates.

5. Role of Water:

• Describe how hydrogen bonds contribute to the unique properties of water.

6. Cellular Impact:

• Predict the potential cellular effects if nucleic acids were damaged.

Level 3 (Critical Thinking & Integration)

7. Alternative Energy Sources:

• If a cell is deprived of carbohydrates, which biomolecule could be used for energy and what metabolic adjustments would be necessary?

8. Structural Variability:

• Given the molecular formula C6H12O6, discuss why this formula can represent different monosaccharides (e.g., glucose, fructose, galactose).

9. Homeostasis Integration:

• How do carbohydrates, proteins, lipids, and nucleic acids work together to maintain homeostasis in a living organism?

• Videos & Lectures:

• Khan Academy Biochemistry Playlist – Offers clear explanations on biomolecules and chemical bonds.

• CrashCourse Biochemistry – Engaging video summaries on biochemistry fundamentals.

• Textbooks & Reading:

• Lehninger Principles of Biochemistry – Provides in-depth details on molecular structures and processes.

• Biochemistry for Dummies (or similar introductory texts) – For quick reviews and simplified explanations.

• Interactive Tools:

• Online molecule viewers (e.g., PubChem or Protein Data Bank) can help you explore 3D structures of molecules.

Use this guide as a roadmap for your study sessions this week. Work through the concepts, answer the questions, and refer to the additional resources to reinforce your understanding. Happy studying!