Chapter 6

• Microorganism


  A "bag" of chemicals that interact with each other in a variety of ways; even the bag itself is composed of chemicals
• Everything a microorganism is and does is related to chemistry
• Organic chemistry


  The study of compounds that contain carbon
• Inorganic chemistry


  Involves all other chemical reactions
• Biochemistry


  The chemistry of living cells - the chemistry of life
• Organic compounds contain carbon
• Organic chemistry is the branch of science that studies organic compounds
• Organic compounds are not necessarily related to living organisms; although some organic compounds are associated with living organisms, many are not
• Examples of what organic chemistry involves

  • Fossil fuels
  • Dyes
  • Drugs
  • Paper
  • Ink
  • Paints
  • Plastics
  • Gasoline
  • Rubber tires
  • Food
  • Clothing
• Carbon atoms


  • Have a valence of 4, meaning that they can bond to four other atoms
• Ways in which carbon atoms can bond to each other

  • Single bond
  • Double bond
  • Triple bond
• Covalent bond


  A pair of electrons is shared
• Chain


  A series of carbon atoms bonded together
• Hydrocarbons


  Organic molecules that contain only carbon and hydrogen atoms
• Simple hydrocarbons


  • [Examples not provided]
• Cyclic compounds


  When carbon atoms link to other carbon atoms to close a chain, they form rings
• Cyclic compound


  • Benzene
• Biochemistry


  The study of biology at the molecular level; the chemistry of living organisms
• Biomolecules


  Molecules present within living organisms, usually large molecules called macromolecules
• Macromolecules


  • Carbohydrates
  • Lipids
  • Proteins
  • Nucleic acids
• Other examples of biomolecules

  • Vitamins
  • Enzymes
  • Hormones
  • Energy-carrying molecules such as adenosine triphosphate (ATP)
• Humans obtain their nutrients from the foods they eat
• Digestion and absorption of nutrients

  1. Carbohydrates, fats, nucleic acids, and proteins contained in foods are digested

  2. Their components are absorbed and carried to every cell in the body

  3. They are then broken down and rearranged in metabolic reactions
• Microorganisms also absorb essential nutrients into the cell by various means
• The nutrients are then used in metabolic reactions as sources of energy and as "building blocks" for enzymes, structural macromolecules, and genetic materials
• Carbohydrates


  Biomolecules composed of carbon, hydrogen, and oxygen (in the ratio 1:2:1)
• Examples of carbohydrates


  • Glucose
  • Fructose
  • Sucrose
  • Lactose
  • Maltose
  • Starch
  • Cellulose
  • Glycogen
• Categories of carbohydrates


  • Monosaccharides
  • Disaccharides
  • Polysaccharides
• Monosaccharides


  The smallest and simplest of the carbohydrates
• Mono


  Refers to the number of rings in the structure
• Glucose


  The most important monosaccharide in nature; may occur as a chain or in alpha or beta ring configurations
• Number of carbon atoms in monosaccharides

  • 2-9 carbon atoms, most contain 5-6
• Triose


  A three-carbon monosaccharide
• Tetrose


  A four-carbon monosaccharide
• Pentose


  A five-carbon monosaccharide
• Hexose


  A six-carbon monosaccharide
• Heptose


  A seven-carbon monosaccharide
• The main source of energy for body cells is glucose
• The three forms of glucose


  • [Examples not provided]
• In humans, glucose is carried in the blood to cells where it is oxidized to produce energy-carrying ATP