2025 NYJC Revision Worksheet H2 Chem Biomolecules Enzymes (Student)

NANYANG JUNIOR COLLEGE H2 Biology Biology remedial Biomolecules and Enzymes J2 1 REVISION WORKSHEET: Topics B and C: BIOMOLECULES & ENZYMES Core Idea 1 – The Cell and Biomolecules of Life Key Words / Phrases (g) Describe the structure and properties of the following monomers: i. α-glucose and β-glucose (in carbohydrates) Structure Properties ii. glycerol and fatty acids (in lipids) Structure Properties iii. amino acids (in proteins) (knowledge of chemical formulae of specific R-groups of different amino acids is not required) Structure Properties

NANYANG JUNIOR COLLEGE H2 Biology Biology remedial Biomolecules and Enzymes J2 2 (h) Describe the formation and breakage of the following bonds (show diagram): i. glycosidic bond Formation: Breakage: ii. ester bond Formation: Breakage: iii. peptide bond Formation: Breakage:

NANYANG JUNIOR COLLEGE H2 Biology Biology remedial Biomolecules and Enzymes J2 3 (i) Describe the structures and properties of the follo wing biomolecules and explain how these are related to their roles in living organisms: i. starch (including amylose and amylopectin) ii. cellulose iii. glycogen Carbohydrates St ructure Functions Starch (storage) Glycogen (Storage) Cellulose (structural)

NANYANG JUNIOR COLLEGE H2 Biology Biology remedial Biomolecules and Enzymes J2 4 iv. triglyceride v. phospholipid Lipids Structure Function Triglyceride Phospholipid (m) Explain primary structure, secondary structure, te rtiary structure and quaternary of proteins, and describe the types of bonds that hold the molecule in shape (hydrogen, ionic, disulfide and hydrophobic interactions) Protein structure Definition Bonds present (between?) Primary Secondary Tertiary Quaternary

NANYANG JUNIOR COLLEGE H2 Biology Biology remedial Biomolecules and Enzymes J2 5 (n) Explain the effects of temperature and pH on protein structure (write on a separate paper) (o) Describe the molecular structure of the following proteins and explain how the structure of each protein relates to the function it plays: i. haemoglobin (transport) ii. collagen (structural) iii. G-protein linked receptor (signalling) (Knowledge of details of the number of amino acids and types of secondary structures present is not required) Proteins Structure Function Haemoglobin Collagen G-protein linked receptor (signaling)

NANYANG JUNIOR COLLEGE H2 Biology Biology remedial Biomolecules and Enzymes J2 6 (p) Explain the mode of action of enzymes in terms of an active site , enzyme-substrate complex, lowering of activation energy and enzyme specificity using the lock-and-key and induced-fit hypotheses. In other words, how do enzymes catalyze s ubstrates? Your answer should include the key words in bold. (q) Investigate and explain the effects of temperature, pH, enzyme concentration and substrate concentration of an enzyme-catalysed reaction by measuring rates of formation of products (e.g. measuring gas produced usi ng catalase) or rate of disappearance of substrate (e.g. using amylase, starch and iodine). Factor Effect on enzyme-c atalyzed rate of reaction (Pls draw graph sketch) Temperature

NANYANG JUNIOR COLLEGE H2 Biology Biology remedial Biomolecules and Enzymes J2 7 pH Enzyme concentration Substrate concentration

NANYANG JUNIOR COLLEGE H2 Biology Biology remedial Biomolecules and Enzymes J2 8 (r) Describe the structure of competitive and non-compet itive inhibitors with reference to the binding sites of the inhibitor. Competitive inhibitors: Non-competitve inhibitors: (s) Explain the effects of competitive and non-compet itive inhibitors (including allosteric inhibitors) on the rate of enzyme activity. Competitive inhibitors Non- competitive inhibitors Allosteric inhibitors