Introduction
In the biology section of NEET, diagram-based questions are commonly asked to assess the understanding and application of concepts. These questions require students to interpret and analyze diagrams, graphs, or charts to answer the related questions. While diagram-based questions can appear in various chapters, there are some topics that typically have a higher number of such questions.

Topics with a High Number of Diagram-Based Questions

1. Human Physiology
- Respiratory System: Diagrams related to the structure of the respiratory system, including lungs, trachea, bronchi, and alveoli, are frequently asked.
- Digestive System: Questions may involve interpreting diagrams of the digestive system, such as the structure of the stomach, intestines, liver, and pancreas.
- Circulatory System: Questions based on diagrams of the heart, blood vessels, and blood flow are commonly found.
- Nervous System: Diagrams related to the structure of neurons, synapses, and various parts of the brain are often included.

2. Genetics and Evolution
- Mendelian Genetics: Questions may require interpretation of Punnett squares, pedigrees, or diagrams representing different types of genetic crosses.
- DNA Structure and Replication: Diagrams illustrating the structure of DNA, replication process, and base pairing are commonly asked.
- Cell Division: Questions based on diagrams of mitosis and meiosis are frequently encountered.
- Evolutionary Concepts: Diagrams illustrating evolutionary processes like natural selection, speciation, and adaptive radiation may be included.

3. Cell Biology
- Cell Structure: Questions may involve interpreting diagrams of various cell organelles such as mitochondria, endoplasmic reticulum, Golgi apparatus, and nucleus.
- Cell Cycle: Diagrams representing different phases of the cell cycle, including interphase, mitosis, and cytokinesis, are commonly asked.

4. Plant Physiology
- Photosynthesis: Diagrams related to the structure of chloroplasts, light-dependent and light-independent reactions, and the Calvin cycle are frequently encountered.
- Plant Hormones: Questions may involve interpreting diagrams depicting the synthesis, transport, and effects of plant hormones like auxins, gibberellins, and abscisic acid.

5. Ecology and Environment
- Ecosystems: Diagrams representing food chains, food webs, and energy flow in ecosystems are commonly asked.
- Biogeochemical Cycles: Questions may involve interpreting diagrams of carbon, nitrogen, or water cycles.
- Pollution and Conservation: Diagrams illustrating the impact of pollution on ecosystems and conservation strategies may be included.

Conclusion
While diagram-based questions can be present in any chapter of the biology section of NEET, topics such as human physiology, genetics and evolution, cell biology, plant physiology, and ecology and environment typically have a higher number of such questions. Students should focus on understanding and analyzing diagrams related to these topics to perform well in NEET.