# 4-mark practice questions — IB DP Biology Higher Level (2023 syllabus)

> 310 questions · biology

## How to answer

4-mark questions are the shortest levels-of-response band. Aim for four scientific ideas, each in its own short sentence.

## Sample questions

1. [Explain how increasing global temperatures can alter the geographical distribution of terrestrial species and describe t…](https://www.gradenine.co.uk/q/explain-how-increasing-global-temperatures-can-34f6e4c7)
2. [Describe the role of the sugar molecule in the structure of nucleic acids and Explain how its variation between DNA and …](https://www.gradenine.co.uk/q/describe-the-role-of-the-sugar-3888e138)
3. [Explain how the cohesive and adhesive properties of water are essential for its transport in the xylem of plants.](https://www.gradenine.co.uk/q/explain-how-the-cohesive-and-adhesive-f505e071)
4. [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)
5. [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)
6. [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)
7. [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)
8. [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)

## 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)
- [Practise with AI marking (free)](https://www.gradenine.co.uk/start)