- Begin by thoroughly understanding the fundamental concepts of physiology in zoology. This includes topics such as cell physiology, organ systems, homeostasis, and physiological adaptations.


- Analyze the previous years' question papers to identify the recurring topics and the level of difficulty of physiology-based questions. This will give you an idea of the important areas to focus on during your preparation.


- Create a structured study plan that covers all the important topics in physiology. Allocate sufficient time to each topic based on its weightage in the syllabus and your level of understanding.


- Use standard textbooks recommended for the zoology optional subject to study physiology. Some popular reference books include "Animal Physiology" by R. Hill, G. Wyse, and M. Anderson, and "Principles of Animal Physiology" by C. Moyes and P. Schulte. These books provide in-depth explanations of various physiological processes.


- While studying, take detailed notes and create mind maps to organize the information. This will help you grasp complex concepts and make it easier to revise later on.


- Physiology-based questions often require the interpretation of diagrams, graphs, and experimental data. Practice solving such questions to improve your analytical and interpretational skills.


- Regularly solve previous years' question papers to familiarize yourself with the exam pattern and the type of questions asked. This will also help you improve your time management skills.


- Participate in online forums and discussion groups related to the UPSC zoology optional subject. Engaging in discussions with fellow aspirants can provide additional insights and perspectives on physiology-based questions.


- Regular revision is crucial to retain the concepts and information related to physiology. Set aside dedicated time for revision and use mnemonic techniques or flashcards to aid memorization.

By following these strategies, you can effectively tackle physiology-based questions in the Zoology Optional subject and enhance your chances of scoring well in the UPSC examination.