Science

• Key molecules that are required to build structures that enable organisms to function

  • Carbohydrates
  • Proteins
  • Lipids
  • Nucleic Acids
  • Water
• Monomers


  Smaller units from which larger molecules are made
• Synthetic polymers


  • nylon
  • polyethylene
  • polyester
  • Teflon
  • epoxy
• Enzyme catalysis


  1. Substrate binding

  2. Transition state facilitation

  3. Catalysis

  4. Release
• Enzymes


  • They increase the rate of chemical reactions without themselves being consumed or permanently altered by the reaction
  • They increase reaction rates without altering the chemical equilibrium between reactants and products
• As temperature increases


  The rate of reaction increases
• Carbohydrates


  Important group of biological molecules that includes sugars and starches
• Carbohydrates contain carbon, hydrogen, and oxygen only
• When large pieces of carbohydrates break down, it turns into glucose
• Monosaccharides


  Simplest carbohydrate and cannot be hydrolyzed (broken down due to water) to produce a smaller carbohydrate molecule

  
• Monosaccharides are the building blocks of carbohydrates

  
• Monosaccharides have 1 chemical structure for the sugar molecule and contain carbon, hydrogen, and oxygen

  
• Monosaccharides contain between 3 and 7 carbon atoms

  
• Aldoses


  Contain an aldehyde (-CHO) functional group at one end (e.g. glucose)
• Ketoses


  Contain a ketone (C=O) functional group usually at C#2 (e.g. fructose)
• Monosaccharides can be in straight or ring structure

  
• Hexoses (6 carbon atoms)

  • Glucose
  • Fructose
  • Galactose

  
• Fructose is the sweetest and can be easily found on fruits and usually used for candies
• Disaccharides


  1 monosaccharide + 1 monosaccharide = 1 disaccharide
• Glycosidic acid


  Bond/glue that connects the two monosaccharides together
• Dehydration synthesis


  Chemical process to combine 2 monosaccharides
• Dehydration synthesis removes H2O to unite the 2 monosaccharides
• Disaccharides


  • Lactose
  • Maltose
  • Sucrose
• Lactose


  Glucose + Galactose - H2O

  
• Lactase is the enzyme found in the stomach that digests dairy products (milk sugar)
• Lactose intolerance occurs when people lack lactase, therefore dairy products are not broken down
• Sucrose


  Glucose + Fructose - H2O

  
• Maltose


  Glucose + Glucose - H2O

  
• Polysaccharides


  Long chains of many monosaccharides joined together by glycosidic bonds

  
• Polysaccharides


  • Starch
  • Glycogen
  • Cellulose

  
• Starch


  Plant storage polysaccharide
• Starch is not a pure substance, but is a mixture of amylose and amylopectin
• Amylase


  Enzymes that can break down amylose and amylopectin into maltose
• Amylopectin is the first to be dissolved as amylose can be stored. The more refined the food, the increase in amylopectin and sugar in the body

  
• Glycogen


  Similar in structure to Amylopectin, made by animals as their storage, and is found mainly in muscle and liver

  
• Glycogen can be mobilized (broken down to glucose for energy) very quickly due to its highly branched structure
• Cellulose


  Only found in plants, where it is the main component of cell walls
• Alternate glucose molecules in cellulose are inverted compared to starch</b>

  
• Cellulose is not a plant storage for energy
• Cellulose forms straight chains