Biomolecules Chapter: Carbohydrates and Proteins

Biomolecules

Carbohydrates

• Definition: Carbohydrates are polyhydroxy aldehydes or ketones or compounds that can be broken down into these.
• Classification:
  • Monosaccharides (simple sugars): glucose, fructose, galactose
  • Disaccharides (double sugars): sucrose, lactose, maltose
  • Polysaccharides (complex sugars): starch, cellulose, glycogen
• Functions:
  • Energy source for cells
  • Structural components of cells
  • Storage molecules

Proteins

• Definition: Proteins are polymers of amino acids
• Classification:
  • Fibrous proteins: keratin, collagen
  • Globular proteins: hemoglobin, albumin
• Structure:
  • Primary structure: sequence of amino acids
  • Secondary structure: alpha-helix, beta-pleated sheet
  • Tertiary structure: 3D shape of protein
  • Quaternary structure: arrangement of subunits
• Functions:
  • Enzymes: catalyze biochemical reactions
  • Hormones: regulate metabolic processes
  • Structural components: muscles, bones, skin

Lipids

• Definition: Lipids are non-polar, hydrophobic molecules
• Classification:
  • Fats: triglycerides
  • Oils: triglycerides
  • Waxes: esters of fatty acids
  • Phospholipids: phosphorus-containing lipids
• Functions:
  • Energy storage
  • Cell membrane structure
  • Hormone production

Nucleic Acids

• Definition: Nucleic acids are polymers of nucleotides
• Classification:
  • DNA (deoxyribonucleic acid)
  • RNA (ribonucleic acid)
• Structure:
  • Double helix (DNA)
  • Single strand (RNA)
• Functions:
  • Genetic information storage
  • Protein synthesis

Enzymes

• Definition: Enzymes are biological catalysts
• Characteristics:
  • High specificity
  • Optimum temperature and pH
  • Activation energy reduction
• Functions:
  • Catalyze biochemical reactions
  • Increase reaction rates

Vitamins

• Definition: Vitamins are essential nutrients required in small amounts
• Classification:
  • Fat-soluble: vitamins A, D, E, K
  • Water-soluble: vitamins B, C
• Functions:
  • Energy metabolism
  • Cell growth and development
  • Antioxidant functions

Biomolecules

Carbohydrates

• Carbohydrates are polyhydroxy aldehydes or ketones that can be broken down into these, serving as an energy source for cells and structural components.
• They are classified into three main categories: monosaccharides (simple sugars like glucose, fructose, and galactose), disaccharides (double sugars like sucrose, lactose, and maltose), and polysaccharides (complex sugars like starch, cellulose, and glycogen).
• Polysaccharides, such as starch, cellulose, and glycogen, act as storage molecules.

Proteins

• Proteins are polymers of amino acids, comprising primary, secondary, tertiary, and quaternary structures.
• They are classified into two main categories: fibrous proteins (like keratin and collagen) and globular proteins (like hemoglobin and albumin).
• Enzymes, which are a type of protein, catalyze biochemical reactions, while hormones regulate metabolic processes, and structural components form muscles, bones, and skin.

Lipids

• Lipids are non-polar, hydrophobic molecules that serve as energy storage units and form cell membrane structures.
• They are classified into four main categories: fats (triglycerides), oils (triglycerides), waxes (esters of fatty acids), and phospholipids (phosphorus-containing lipids).
• Phospholipids, in particular, form the structure of cell membranes, while some lipids are involved in hormone production.

Nucleic Acids

• Nucleic acids, including DNA and RNA, are polymers of nucleotides that store genetic information and facilitate protein synthesis.
• DNA has a double helix structure, whereas RNA is a single-stranded molecule.
• Genetic information is stored in DNA, which is essential for protein synthesis and cell growth.

Enzymes

• Enzymes are biological catalysts that reduce activation energy, increasing reaction rates, and are highly specific to their substrates.
• Enzymes have optimum temperature and pH conditions, and their high specificity is essential for catalyzing biochemical reactions.
• They play a crucial role in increasing reaction rates, making them essential for biological processes.

Vitamins

• Vitamins are essential nutrients required in small amounts, classified into two main categories: fat-soluble (vitamins A, D, E, and K) and water-soluble (vitamins B and C).
• Vitamins are involved in energy metabolism, cell growth, and development, and have antioxidant functions, making them essential for maintaining overall health.

Learn about the definition, classification, and functions of carbohydrates and proteins, including their roles in cells and organisms.