Organic Chemicals of Life

Organic Chemicals of Life

• 96% of human body mass is composed of oxygen, carbon, hydrogen, and nitrogen, primarily in water (H₂O).
• Most important compounds are macronutrients, required in large amounts, providing energy (calories).
  • Examples include carbohydrates, proteins, and fats.
• Micronutrients, or trace elements, are also essential but needed in smaller amounts.
  • Examples include vitamins and mineral salts.
• Chemicals of life are grouped into:
  • Organic compounds
  • Inorganic compounds

Organic Chemicals of Life - Examples

• Proteins: Long chains of amino acids linked by peptide bonds.

  • Essential amino acids (cannot be made by the body) come from food.
  • Non-essential amino acids are produced by the body.

• Vitamins: Organic compounds needed in small amounts for proper metabolic function, cell function, growth, and development.

  • Some examples are Vitamin A, B1, B2, B3, B6, B12, C, D, E, and K.

• Nucleic acids (DNA & RNA): Molecules of life critical for reproduction, growth, development, protein synthesis, and metabolic processes

• Carbohydrates: Simple sugars (monosaccharides; e.g., glucose, fructose, galactose), double sugars (disaccharides; e.g., sucrose, lactose), and complex sugars (polysaccharides; e.g., starch, cellulose, glycogen).

• Lipids: Fats, oils, and waxes; important for energy storage, cell structure, and hormone production. Types include fatty acids, glycerides, non-glyceride lipids, and complex lipids (like lipoproteins and glycolipids).

Inorganic Chemicals of Life

• Water
• Mineral salts
• Gases (oxygen)
• Acids & bases

Carbohydrates - Structure

• Monosaccharides: Single sugar units (e.g., glucose, fructose, galactose).
• Disaccharides: Two sugar units joined together (e.g., sucrose, lactose, maltose).
• Oligosaccharides: Three to ten sugar units (e.g., raffinose, stachyose).
• Polysaccharides: Many sugar units joined together (e.g., starch, cellulose, glycogen).

Carbohydrates - Functions

• Primary energy source for cells
• Storage of energy (glycogen)
• Component of cell structures (e.g., cellulose in plant cell walls)
• Part of other biomolecules (e.g., glycoproteins, glycolipids)

Glucose

• Main sugar metabolized in the body for energy (ATP).
• Blood glucose levels must be maintained within a narrow range.
• Insulin converts excess glucose into glycogen for storage.
• Glucagon converts glycogen to glucose when needed.

Disaccharides

• Types include sucrose, lactose, and maltose.
• Formed by the joining of two monosaccharides via a glycosidic bond.
• Examples include sucrose (glucose + fructose), lactose (glucose + galactose), and maltose (glucose + glucose)

Lactose Intolerance

• Inability to fully digest lactose due to a deficiency in the enzyme lactase.
• Characterized by symptoms like abdominal cramps, bloating, and diarrhea when consuming dairy products.

Oligosaccharides

• Three to ten simple sugar units present in beans, legumes, and other foods
• Unique glycosidic bonds prevent absorption by the small intestine
• Metabolized by bacteria in the large intestine to produce gas/bloating

Dietary Fiber

• Indigestible polysaccharides (cellulose, hemicellulose, pectin, gum).
• Insoluble and soluble types
• Helps with maintaining digestive health through easier defecation, reducing constipation and problems related to the colon

Lipids

• Fats, oils, and waxes
• Four main groups: fatty acids, glycerides, non-glycerides, and complex lipids.

Triglycerides

• Major energy reserve in the body, storing unused calories in the form of fats
• Composed of glycerol and three fatty acids.
• Excess triglycerides can increase the risk of heart attacks.
• Sources include foods with saturated or unsaturated fats.

Cholesterol

• Waxy substance, a type of steroid.
• Needed for cell membranes, hormones, and vitamin D.
• High levels can increase the risk of heart disease due to buildup of LDLs creating plaque
• Cholesterol carried in bloodstream via lipoproteins are of two types LDL (bad) and HDL (good), with LDL depositing and causing plaque buildup.

Essential Fatty Acids

• The body cannot manufacture certain fatty acids and thus are considered essential fatty acids that need to be taken in through diet (e.g omega-3, omega-6)

Phospholipids

• Major component of cell membranes, forming a bilayer structure
• Consist of a glycerol molecule, two fatty acids, and a phosphate head group.
• Hydrophilic head and hydrophobic tails are key features for bilayer formation
• Essential for cell membrane integrity.

Steroids

• A type of lipid that includes hormones like cortisol, estrogen, and testosterone
• Structurally characterized by a specific four-ring structure
• Important in cell signaling and various physiological processes.
• Cholesterol is a major steroid found in animal tissues.

Nucleic Acids

• DNA (deoxyribonucleic acid) and RNA (ribonucleic acid)
• Store and process genetic information.
• DNA stores the genetic code.
• RNA plays an important role in protein synthesis.

High Energy Compounds

• Adenosine Triphosphate (ATP) is the primary energy currency in the body.
• Used by cells for various metabolic activities; muscles contraction.
• Guanosine triphosphate (GTP) is another important high-energy molecule also involved in metabolic activities.

Functions of Nucleic Acids - DNA and RNA

• DNA is responsible for storing and transferring genetic information to new cells
• DNA fingerprinting is a chemical test that shows the genetic makeup of an individual.
• Functions in crime, paternity, disease diagnosis, vaccine development, and cancer research.
• RNA plays important roles in protein synthesis and gene regulation.

Genetically Modified Organisms (GMOs)

• Organisms with altered genetic material via genetic engineering
• Used for various purposes, such as pharmaceutical production, disease resistance in crops, and genetic research.
• GMOs contain foreign genes inserted to introduce specific traits.

Gene Therapy

• Technique using genetic engineering to treat hereditary diseases by replacing defective genes with normal ones
• Includes bacterial, viral, and other delivery systems to insert genes into target cells
• Application for various medical conditions, but not without potential side effects
• Recombinant DNA technology uses genetically modified bacteria for large-scale insulin production; vaccines and interferons also produced through this technology.