Biochemistry 101: Introduction

Biochemistry 101: Introduction

• Biochemistry studies chemistry in living organisms.
• It applies chemistry to study biological processes at the cellular and molecular levels, including structure, composition, and chemical reactions.
• Biochemistry can be seen as biology plus chemistry.

Molecular Biology

• Molecular biology studies gene structure and functions.
• It operates at the molecular level and explores the molecular basis of hereditary, genetic variation, and gene expression patterns.
• It involves the study of molecular structures in DNA.

Immunochemistry

• Immunochemistry studies the molecular mechanisms underlying the immune system
• It focuses on the nature of antibodies, antigens, and their interactions.
• It explores how the immune system responds through chemical reactions, as the body communicates through these reactions.

Neurochemistry

• Neurochemistry studies neurochemicals influencing neuron function and forming neural networks
• In simpler terms, it's the study of communication in the brain through chemical reactions.

Bioinorganic Chemistry

• Bioinorganic chemistry focuses on the roles of metals and non-metals in biological processes
• Metal ions are required for processes like respiration, metabolism, nitrogen fixation, photosynthesis, nerve transmission, muscle contraction, and protection against toxins.
• Highlights the intersection of inorganic chemistry and biochemistry.

Bioorganic Chemistry

• Bioorganic chemistry combines organic chemistry and biochemistry
• Deals with biological processes using chemical methods for proteins, enzymes, lipids, and carbohydrates.
• It represents the intersection of biochemistry and organic chemistry.

Biochemical Importance

• Biochemical studies have greatly enhanced understanding of health and disease, opening new areas in biochemistry.
• Life depends on biochemical reactions and processes.
• Biochemistry and medicine are interconnected. Genetic diseases, sickle cell anemia, atherosclerosis, and diabetes mellitus relate to nucleic acids, proteins, lipids, and carbohydrates.

Organization Levels of the Human Body

• Atom: The smallest unit of matter with the characteristic properties of a chemical element.
• Ions: atoms or groups of atoms with a positive or negative charge formed by gaining or losing electrons, but never protons.
• Anions: negatively charged ions formed when atoms gain electrons; non-metals typically form anions.
• Cations: positively charged ions formed when atoms lose electrons; metals typically form cations.

Key Electrolytes and Their Functions

• Sodium (Na+): regulates fluid balance and aids nerve and muscle function.
• Potassium (K+): regulates fluid balance and aids nerve and muscle function.
• Chloride (Cl-): regulates fluid balance and helps maintain proper pH balance in the body.
• Calcium (Ca2+): essential for healthy bones and teeth, aids in nerve and muscle function.
• Magnesium (Mg2+): aids in muscle and nerve function and helps regulate blood sugar levels.
• Phosphorus (PO43-): essential for healthy bones and teeth, aids in cell growth and repair.
• Bicarbonate (HCO3-): helps maintain proper pH balance in the body and acts as a buffer system.

Evolution and Elemental Composition

• Earth solidified approximately 4 billion years ago.
• There are 81 stable elements.
• Living organisms contain:
  • 11 elements with large concentration: H, C, N, O, Na, Mg, P, S, Cl, K, Ca.
  • 7 elements with small concentration: Mn, Fe, Co, Cu, Zn, I, Mo.
  • 7 elements found in a few species: B, F, Si, V, Cr, Se, Sn.

Elemental Composition of the Human Body

• Oxygen (O): 63%
• Carbon (C): 25.5%
• Hydrogen (H): 9.5%
• Nitrogen (N): 1.4%
• Calcium (Ca): 0.31%
• Phosphorus (P): 0.22%
• Potassium (K): 0.08%
• Sulfur (S): 0.06%

Metal Content in a 70 kg Human Body

• Calcium (Ca): 1000 g
• Potassium (K): 140 g
• Sodium (Na): 100 g
• Magnesium (Mg): 25 g
• Iron (Fe): 4.2 g
• Zinc (Zn): 2.3 g
• Copper (Cu): 72 mg
• Tin (Sn) and Vanadium (V): 20 mg
• Chromium (Cr): 14 mg
• Manganese (Mn): 12 mg
• Molybdenum (Mo): 5 mg
• Cobalt (Co): 3 mg
• Nickel (Ni): 1 mg
• Non-metals: O (45500 g), C (12600 g), H (7000 g), N (2100 g), P (700 g).

Molecules

• Molecules are groups of atoms forming a functional group (radicals).
• Examples include:
  • Glucose
  • Fatty Acids
  • Amino Acids
  • Nucleotides

Macromolecules

• Macromolecules are groups of molecules forming a chemical structure.
• Examples include:
  • Glucose = Carbohydrates
  • Fatty Acids = Lipids
  • Amino Acids = Proteins
  • Nucleotides = Nucleic Acid

Mass Composition of the Human Body

• 65% water (H2O)
• 20% proteins
• 12% lipids
• ~1.5% nucleic acids
• ~1.5% inorganic molecules (mineral salts)

Biological Structures

• Cells: Building blocks of life made from macromolecules.
• Tissue: A group of cells clumping together to function as a whole tissue.
• Organ: A group of tissue networks functioning as a specific role in the body.
• Organ System: A group of organs network with neighboring organs to create a system of the body.