Playbook
Biomolecules
88 q - 2.17/paper - 2% HARD. Sugars and their linkages, amino acids, and the bases of DNA and RNA.
- Questions in the bank
- 88
- q/paper (2024–25 papers)
- 2.17
- Tagged HARD
- 2%
- Subtopics
- 5
Strand: Recall
When you’ll see it
A sugar, its linkage or whether it reduces Fehling's; an amino acid or peptide; a DNA or RNA base; a vitamin or enzyme.
How this chapter is tested
88 q at 2.17 a paper, 2% HARD. Amino acids and proteins (27 q, never HARD): essential amino acids, the peptide bond, and protein structure levels. Carbohydrates (21 q) and glycosidic linkages (19 q): which sugars reduce Fehling's and Tollens', and which link joins which units.
Nucleic acids (16 q) are the bases — adenine, guanine, cytosine in both; thymine in DNA, uracil in RNA — and the sugar, deoxyribose or ribose.
The sub-skills
The distinct skills inside the chapter, in the order to learn them.
Linkages
Sucrose α1–β2 (non-reducing), maltose α1–4, lactose β1–4, cellulose β1–4, starch α1–4 with α1–6 branches.
Reducing sugars
A free hemiacetal group reduces Fehling's; sucrose has none.
Nucleic acids
DNA: A, G, C, T and deoxyribose; RNA: A, G, C, U and ribose.
Traps to expect
Distractor shapes this chapter reuses. The Traps page covers the patterns that cut across chapters.
Sucrose as a reducing sugar
Sucrose's link joins both anomeric carbons, so it does NOT reduce Fehling's — the planted answer in 'which is non-reducing'.
Thymine in RNA
Uracil replaces thymine in RNA.
Learn it before you drill it
This chapter has full teaching notes — foundations, worked examples, self-checks and a per-subtopic mastery checkpoint. Read the notes once, then drill subtopic by subtopic below.
Biomolecules notesDrill every biomolecules question
88 questions from the bank, scoped to 5 bundled subtopics.
Drill one subtopic at a time
The 5 subtopics this playbook covers, in catalog order.
Related playbooks
Often paired with this one — the technique, the trap or the taxonomy overlaps. Drill these next.