B1

• Form and Function - Molecules


  Variety of compounds containing Carbon

  
• 4 biochemical groups


  • Carbohydrates
  • Lipids
  • Proteins
  • Nucleic acids

  
• Covalent Bonds


  For H, O, N, C, P
• Hydrolysis


  1. Digestion breaks down macromolecules by breaking covalent bonds between monomers

  2. Use water
• Condensation reactions


  1. Form covalent bonds between monomers to build macromolecules

  2. Releases Water
• Condensation of two monosaccharides to disaccharide


  • Glucose + galactose —→ lactose + water

  
• Condensation of nucleotide components to make DNA or RNA nucleotide


  • Glucose + galactose —→ lactose + water

  
• Hydrolysis of disaccharides into two monosaccharides


  Lactose + water ⟶ glucose + galactose

  
• Peptide bond


  OCNH between two amino acids catalyzed by an enzyme
• Monosaccharides


  Pentose (e.g. Ribose) and Hexose (e.g. Glucose)

  
• Glucose molecule


  • Polar due to 5 OH bonds
  • Stable due to strong covalent bonds
  • High solubility in H2O
  • Easily transportable
  • Yields a lot of energy when bonds are broken
• Polysaccharides


  Starch and Glycogen for energy storage
• Starch


  • Large and not soluble in water
  • Large but compact
• Amylose


  Bonded to #1C as well as to #4C of adjoining glucose molecule (α-1,4 linkage)

  
• Amylopectin


  Has α-1,6 linkages where #1C is bonded to #6C from adjoining molecule

  
• Glycogen


  Made up of glucose monomers with more frequent branches than amylopectin

  
• Cellulose


  Uses beta form of glucose, with β-1,4 linkages, forming linear polymers with no branches

  
• Cellulose


  • Important for cell walls of plants
  • Most abundant molecule on the planet
  • Fibers formed, which run parallel to each other, forming Hydrogen bonds between each layer

  
• Glycoproteins


  Carbohydrate + protein, responsible for cell to cell communication, transport, adhesion, catalysis, and recognition
• Glycoproteins and ABO blood types


  • Red blood cells have either type A or B antigens (glycoprotein) on their plasma membrane
  • People with type AB have both A and B antigens
  • People with type O have neither A nor B antigens
  • People with type A or B have either A or B antigens
  • O blood type can donate to anyone
  • AB type can receive from any blood type
• Lipids


  Non polar, not soluble in water but soluble in other non-polar solutions (e.g. fats, oils, waxes)

  
• Lipids reaction (condensation)


  1 glycerol + 3 fatty acids → 1 triglyceride + 3 water molecules

  
• Phospholipids formation


  1 glycerol + 2 fatty acids + 1 phosphate group → 1 phospholipid + 3 water molecules

  
• Saturated fatty acids


  • Contain single bonds between each carbon, have high melting temp (e.g. animal fats, butter)
• Monounsaturated fatty acids


  • Have one double bond between the carbons, have lower melting temp than saturated (e.g. some plants and animals)
• Polyunsaturated fatty acids


  • Have more than one double bond between the carbons, have relatively low melting point (e.g. many plants)

  
• Adipose tissue


  Formed from many molecules of triglycerides, used to supply energy and for long-term energy storage, makes twice as much energy as carbohydrates, used in endotherms to maintain stable temperature
• Phospholipid bilayer


  • Hydrophobic tails, hydrophilic heads, amphipathic in nature, foundation of a plasma membrane
• Steroid Hormones


  Chemical messengers produced by multiple glands and released into the body, e.g. oestradiol and testosterone
• Amino acids


  Around 20 amino acids in nature, can be drawn with common structure
• Condensation reactions bond amino acids together


  Amino acid 1 + amino acid 2 → Dipeptide + water

  
• Essential amino acids


  Body can produce 11/20 amino acids, 9 need to come from diet
• Polypeptides


  • Vast variety possible due to 20 different amino acids, varying length, and any order
  • Examples: hemoglobin, keratin, lipase, collagen, histones, insulin

  
• Effect of temperature on enzyme activity
• Amino acids


  Molecules that are the building blocks of proteins
• Amino acids


  • Around 20 amino acids found in nature
  • Can be drawn

  
• Condensation reactions


  1. Bond amino acids together

  2. Amino acid 1 + amino acid 2 → Dipeptide + water

  
• Essential amino acids


  9 amino acids that the body cannot produce and must come from diet
• Polypeptides


  A huge variety is possible due to 20 different amino acids, varying lengths, and any order
• Polypeptides


  • Hemoglobin
  • Keratin
  • Lipase
  • Collagen
  • Histones
  • Insulin