# "Explain" questions — IB DP Biology Higher Level (2023 syllabus)

> 305 questions · biology

## How to answer

WHAT + WHY. Every point paired with a because. Structure: X happens because Y. This causes Z because … Assessment Objective: AO2. Every "explain" answer on this spec is marked against exactly this pattern.

## Sample questions

1. [Explain how cyclic photophosphorylation differs from non-cyclic photophosphorylation in terms of the electron pathway an…](https://www.gradenine.co.uk/q/explain-how-cyclic-photophosphorylation-differs-from-023972ef)
2. [Explain how the fluid mosaic model accounts for the lateral movement of membrane proteins and discuss why this movement …](https://www.gradenine.co.uk/q/explain-how-the-fluid-mosaic-model-02b277fa)
3. [Explain how natural selection acts on variation within a population to bring about evolutionary change over successive g…](https://www.gradenine.co.uk/q/explain-how-natural-selection-acts-on-057bf882)
4. [Explain how the structure of prokaryotic ribosomes differs from that of eukaryotic ribosomes, and outline the significan…](https://www.gradenine.co.uk/q/explain-how-the-structure-of-prokaryotic-06ba8415)
5. [Explain how the chemiosmotic gradient across the inner mitochondrial membrane is established and used to synthesise ATP …](https://www.gradenine.co.uk/q/explain-how-the-chemiosmotic-gradient-across-07d76440)
6. [Explain how the structure of the nuclear envelope is related to its function in regulating communication between the nuc…](https://www.gradenine.co.uk/q/explain-how-the-structure-of-the-08b153fd)
7. [Explain how the structure of a chloroplast is related to its function in photosynthesis.](https://www.gradenine.co.uk/q/explain-how-the-structure-of-a-08f7bb80)
8. [Explain how the ultrastructure of a myelinating Schwann cell is adapted for its function in the peripheral nervous syste…](https://www.gradenine.co.uk/q/explain-how-the-ultrastructure-of-a-0aaeeb6e)

## Related

- [IB DP Biology Higher Level (2023 syllabus) revision notes](https://www.gradenine.co.uk/learn/ib-dp-biology-higher-level-2023-syllabus)
- [IB DP Biology Higher Level (2023 syllabus) past papers](https://www.gradenine.co.uk/past-papers/ib-dp-biology-higher-level-2023-syllabus)
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