Essential Idea:  Living Organisms control their composition by complex web of chemical reactions.
At SHS, Topic 2.1 is taught in the following class unit(s):
2.1.U1  Molecular biology explains living processes in terms of the chemical substances involved.
  • Define “molecular biology.”
  • Compare the benefits of a reductionist vs. systems approach to studying biology.
  • Recognize common functional groups.
  • Draw skeletal molecular structures from full structure diagrams.
2.1.U2  Carbon atoms can form four covalent bonds allowing a diversity of stable compounds to exist.
  • Outline the number and type of bond carbon can form with other atoms.​
2.1.U3  Life is based on carbon compounds including carbohydrates, lipids proteins and nucleic acids.
  • List the four major classes of carbon compounds used by living organisms.
2.1.U4  Metabolism is the web of all the enzyme-catalyzed reactions in a cell or organism.
  • Define metabolism and catalysis.
  • State the role of enzymes in metabolism.
2.1.U5  Anabolism is the synthesis of complex molecules from simpler molecules including the formation of macromolecules from monomers by condensation reactions.
  • Define anabolism, monomer and polymer.
  • Describe condensation (dehydration synthesis) reactions.
  • Using simple shapes to represent monomers, diagram a condensation reaction.​
2.1.U6  Catabolism is the breakdown of complex molecules into simpler molecules including the hydrolysis of macromolecules into monomers.
  • Define catabolism.
  • Contrast anabolism and catabolism.
  • Describe hydrolysis reactions.
  • Using simple shapes to represent monomers, diagram a hydrolysis reaction.
2.1.A1  Urea as an example of a compound that is produced by living organisms but can also be artificially synthesized.
  • Draw the molecular structure of urea.
  • Describe how urea can be synthesized by living and artificial mechanisms.
2.1.S1  Drawing molecular diagrams of glucose, ribose, a saturated fatty acid and a generalized amino acid. 
*for carbohydrates
* for lipids
  • Draw the molecular diagram of ribose.
  • Draw the molecular diagram of alpha-glucose.
  • Draw the molecular diagram of a saturated fatty acid.
  • Identify the carboxyl and methyl groups on a fatty acid.
  • Draw the generalized structure of an amino acid.
  • Label the amine group, carboxyl group, alpha carbon and R group on an amino acid.​
2.1.S2  Identification of biochemical such as sugars, lipids, or amino acids from molecular drawings.
​*for carbs
​*for lipids
  • Identify the four major classes of carbon compounds used by living organisms from given diagrams (examples will include D-ribose, alpha glucose, beta glucose, trigylcerides, phospholipids and steroids).
  • State the generalized chemical formula of the carbohydrates.
  • Identify the following carbohydrates from molecular drawings:  D-ribose, alpha glucose, beta glucose, cellulose, glycogen, amylose starch and amylopectin starch.
  • Compare the relative amount of oxygen atoms in lipids to the amount in carbohydrates.
  • Identify the following lipids from molecular drawings:  triglycerides, phospholipids and steroids.​
2.1.NOS  Falsification of theories- the artificial synthesis of urea helped to falsify vitalism.
  • Define vitalism.
  • Explain the role of urea in the falsification of vitalism.
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"When we try to pick out anything by itself, we find it hitched to everything else in the Universe." 
 John Muir,   1911