IB Exam (Unit 2)

U1: What does Molecular Biology teach us?

explains living processes in terms of the chemical substances involved

U2: What about Carbon makes it so useful?

• can form four covalent bonds

  • allows a diversity of stable compounds to exist

U3: State what life is based on. List examples of it.

• Life is based on carbon

Examples:

• carbohydrates

• lipids

• proteins

• nucleic acids

U4: Outline Metabolism in relation to Molecular Biology.

the web of all the enzyme-catalyzed reactions in a cell or organism

U5+6: Define Catabolism and Anabolism

Catabolism: the breakdown of complex molecules → simpler molecules

• the hydrolysis of macromolecules into monomers

Anabolism: the synthesis of simpler molecules → complex molecules

• formation of macromolecules from monomers by condensation reactions

A1: Outline how urea is an example of a compound that is produced by living organisms but can also be artificially synthesized

• Theory of Vitalism believed vital forces gave living things life

• urea is found in urine

  • believed to only be created through vital forces

• Wöhler creates it artificially using silver isocyanate and ammonium chloride

• begins disproving vitalism

A1:

S: Draw a molecular diagram of glucose

• hexagon

  • 5Cs and 1O

• C #5 has a CH2OH

• C #3 has a OH on top

S: Draw a molecular diagram of ribose

• pentagon (4C and 1O)

• side chain with one -OH and 2 -H

• side chan with lone H

S: Draw a molecular diagram of a Saturated Fat

can also be written as:

H-(CH₂)_n-COOH

S: Draw a molecular diagram of an Amino Acid

• H = hydrogen atom

• NH or NH₂ amine group

• (-COOH) = carboxyl group

• R = r group or radical

U: Identify the qualities of a Sugar

U: Identify the qualities of a lipid

• have two or three hydrocarbon chains

• the quadruple ring structure of steroids

• Hydrocarbon chains often shown as a zigzag line

• rings of carbon atoms shown as hexagons or pentagon

U: Identify the qualities of a protein

• H = hydrogen atom

• NH or NH₂ = amine group

• (-COOH) = carboxyl group

• R = r group or radical

• Look for bond between N-H (peptide bond)