Biomolecules and Carbohydrates Quiz

Biomolecules

• Biomolecules are organic compounds in living systems, typically composed of carbon, hydrogen, oxygen, and/or nitrogen.
• Carbohydrates are primarily composed of carbon, hydrogen, and oxygen, existing as linear or cyclic structures, providing energy for organisms.

Carbohydrates - Functions

• Providing energy and regulating blood glucose levels
• Sparing protein use for energy
• Breaking down fatty acids and preventing ketosis
• Supporting biological recognition processes
• Acting as flavor and sweeteners, contributing to dietary fiber.

Carbohydrates - Classification

Monosaccharides

• These are the building blocks of carbohydrates.
• Examples include glucose (blood sugar), fructose (fruit sugar), and galactose (brain sugar).
• Formula: C₆H₁₂O₆.

Disaccharides

• Formed by combining two monosaccharides.
• Examples include sucrose (cane sugar; fructose + glucose), lactose (milk sugar; galactose + glucose), and maltose (malt sugar; glucose + glucose).
• Formula: C₁₂H₂₂O₁₁
• The formation of a disaccharide involves dehydration, producing water.

Polysaccharides

• Long chains of monosaccharides.
• Starch is a major energy source for humans, found in rice, corn, potatoes, and wheat (formula (C₆H₁₀O₅)_x).
• Cellulose is a structural component of plant cell walls and wood.

Proteins

• Considered the most abundant and complex biomolecules in organisms, composed of amino acids.

Proteins - Function

• Acting as catalysts (enzymes)
• Providing structural support
• Supporting immune function (antibodies)
• Facilitating active and passive transport
• Driving muscle contraction
• Sending signals in the body

Proteins - Amino Acids

Essential Amino Acids

• Needed by organisms but not produced by the body.
• Examples include histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine.

Nonessential Amino Acids

• Produced by the body.
• Examples include alanine, arginine, asparagine, aspartic acid, cysteine, glutamic acid, glutamine, glycine, proline, serine, and tyrosine.

Protein Structures

• Primary structure: Sequence of amino acids linked by peptide bonds.
• Secondary structure: Regular folding patterns (alpha-helix, beta-pleated sheet) stabilized by hydrogen bonds.
• Tertiary structure: Three-dimensional arrangement of a polypeptide chain.
• Quaternary structure: Arrangement of multiple polypeptide chains.

Protein Important Processes

• Hydrolysis: Breaking down proteins into amino acids using water.
• Denaturation: Disruption of a protein's structure due to factors like heat, pH, or detergents.
• Dissolution: Protein solubility depends on its isoelectric point.

Nucleic Acids

• Informational molecules, encoding genetic instructions and directing protein synthesis.
• Composed of nucleotides.
  • Nucleotides contain a phosphate group, a five-carbon sugar, and a nitrogenous base.
    • Purines (double ring): Adenine, Guanine
    • Pyrimidines (single ring): Cytosine, Thymine, Uracil
• DNA (deoxyribonucleic acid) is double-stranded and stores genetic information.
• RNA (ribonucleic acid) is single-stranded and involved in protein synthesis.

Lipids

• Fatty acids with long chains of saturated or unsaturated hydrocarbon chains joined to a glycerol compound
• Not soluble in water, non-polar compounds.
• Oxidized to release large amounts of energy
• Chemical messengers, energy storage, important component of cell membranes and insulation
  • Fatty acids: Carboxylic acids, structural components of fats, oils, and other lipid categories (saturated/unsaturated)
  • Simple/homolipids: Esters of fatty acids and various alcohols, including fats, oils (triglycerides), and waxes
  • Compound/heterolipids: Esters of fatty acids, alcohols with additional components like phosphoric acid, carbohydrates, or nitrogenous bases including phospholipids, glycolipids.
  • Derived Lipids: Derivatives from simple and compound lipids like steroids and carotenoids, often containing non-hydrolyzable components like steroids (chemical messengers) and carotenoids (pigments)