A Levels Biology (9700)•9700/12/M/J/23
Explanation
Cellulose's Linear and Unreactive Structure
Steps:
- Recall cellulose is a polysaccharide made of glucose units linked by β-1,4-glycosidic bonds.
- Identify its structure as straight, unbranched chains forming strong fibers.
- Note its chemical inertness due to hydrogen bonding, making it unreactive.
- Compare options to match unbranched, linear, and unreactive traits.
Why D is correct:
- Cellulose consists of unbranched β-1,4-glucose chains stabilized by hydrogen bonds, rendering it chemically unreactive, as per its biochemical definition.
Why the others are wrong:
- A: Cellulose is unbranched, not branched like glycogen.
- B: Omits cellulose's unreactive nature from tight hydrogen bonding.
- C: Cellulose is unreactive, not reactive, due to its crystalline structure.
Final answer: D
Topic: Carbohydrates and lipids
Practice more A Levels Biology (9700) questions on mMCQ.me