State two advantages of a carbon atom being able to form four bonds to neighbouring atoms.
[2 marks]
List three carbon compounds that living organisms are based upon.
[3 marks]
State which part of metabolism is occurring at II in the flowchart below.
[1 mark]
State the aspect of the molecular behaviour of water that is used to explain why it is highly important to living organisms.
[1 mark]
Two of the properties of water are its cohesive and adhesive forces.
Describe how these properties are useful to living organisms.
[3 marks]
Both water and methane are small molecules containing single covalent bonds between their atoms.
State two differences between these two molecules that make their physical properties very different.
[2 marks]
List two physical properties, associated with their state of matter, that differ between water and methane.
[2 marks]
Draw a labelled diagram of a water molecule.
[3 marks]
Identify which of the diagrams below is a lipid, giving one reason why.
[2 marks]
Draw a molecular diagram of D-ribose.
[2 marks]
List, using simplified notation, two of the chemical groups found in a generalised amino acid.
[2 marks]
State, giving one reason, which diagram shows the structure of a saturated fatty acid.
[2 marks]
One mark is available for clarity of communication throughout this question.
Outline the theory that states that organic molecules could only be derived from living systems.
[3 marks]
Distinguish between anabolic and catabolic reactions.
Include one example of each reaction.
[5 marks]
Describe the properties of water molecules that enable them to transport metabolites, using four named examples.
[7 marks]
