Nature of science:
Falsification of theories—the artificial synthesis of urea helped to falsify vitalism. (1.9)
Understandings:
Molecular biology explains living processes in terms of the chemical substances involved.
Carbon atoms can form four covalent bonds allowing a diversity of stable compounds to exist.
Life is based on carbon compounds including carbohydrates, lipids, proteins and nucleic acids.
Metabolism is the web of all the enzyme-catalysed reactions in a cell or organism.
Anabolism is the synthesis of complex molecules from simpler molecules including the formation of macromolecules from monomers by condensation reactions.
Catabolism is the breakdown of complex molecules into simpler molecules including the hydrolysis of macromolecules into monomers.
Applications and skills:
Application: Urea as an example of a compound that is produced by living organisms but can also be artificially synthesized.
Skill: Drawing molecular diagrams of glucose, ribose, a saturated fatty acid and a generalized amino acid.
Skill: Identification of biochemicals such as sugars, lipids or amino acids from molecular diagrams.