The OCR GCSE Biology Paper 4 (June 2022) covers advanced topics including photosynthesis, the nervous system, and antibiotic resistance. Key themes include practical investigations into stomatal density, bacterial cultures, and plant starch storage. The paper explores the advantages of chloroplast retention in sea slugs, genetic modification in zebra fish, and the effectiveness of vaccines. It emphasizes data analysis, experimental design, and ethical considerations in biotechnology and conservation. Environmental issues such as microplastics and the impact of human activities on biodiversity are also addressed, highlighting the integration of theoretical and applied biology.