IIT Madras, the organising institute for GATE 2027, has revised the Life Sciences (XL) syllabus. The sections have new codes: XL0 Chemistry is common to everyone, and you choose any two of XL1 to XL5 in the exam. Earlier GATE papers used the codes XL-P to XL-U, so older syllabus guides and books may not match. This page summarises the official 2027 syllabus and exam pattern.
GATE XL 2027 exam pattern
| Part | Marks |
|---|---|
| General Aptitude (10 questions) | 15 |
| XL0 Chemistry (common to all XL candidates) | 25 |
| Two sections of your choice from XL1 to XL5 | 2 × 30 = 60 |
| Total (65 questions, 3 hours) | 100 |
- Question types: multiple choice (MCQ), multiple select (MSQ) and numerical answer type (NAT). Each question carries 1 or 2 marks.
- Choosing sections: you pick your two XL sections during the exam.
The six XL sections
XL0 (orange) is compulsory. Choose any two of XL1 to XL5.
- XL0.1 Atomic Structure and Periodicity
- XL0.2 Structure and Bonding
- XL0.3 s, p and d Block Elements
- XL0.4 Bioinorganic Chemistry
- XL0.5 Chemical Equilibria
- XL0.6 Electrochemistry
- XL0.7 Reaction Kinetics
- XL0.8 Thermodynamics
- XL0.9 Structure-Reactivity Correlations and Organic Reaction Mechanisms
- XL0.10 Chemistry of Biomolecules
- XL1.1 Structure and Function of Biomolecules
- XL1.2 Enzymes and General Principles of Metabolism
- XL1.3 Metabolic Pathways and Associated Disorders
- XL1.4 Analytical Techniques
- XL1.5 Cell Structure and Function
- XL1.6 Gene Expression and Its Regulation, and DNA Repair
- XL2.1 Plant Systematics
- XL2.2 Plant Anatomy
- XL2.3 Plant Development; Cell and Tissue Morphogenesis
- XL2.4 Plant Physiology and Biochemistry
- XL2.5 Genetics and Genomics
- XL2.6 Plant Breeding, Genetic Modification, Genome Editing
- XL2.7 Economic and Applied Botany
- XL2.8 Plant Pathology
- XL2.9 Ecology and Environment
- XL3.1 Historical Perspective
- XL3.2 Methods in Microbiology
- XL3.3 Microbial Taxonomy and Diversity
- XL3.4 Prokaryotic Cells: Structure and Function
- XL3.5 Microbial Growth
- XL3.6 Microbial Metabolism
- XL3.7 Microbial Diseases and Host Pathogen Interaction
- XL3.8 Control of Micro-organisms: Chemotherapy/Antibiotics
- XL3.9 Microbial Genetics
- XL3.10 Microbial Ecology
- XL4.1 Animal Diversity
- XL4.2 Evolution
- XL4.3 Genetics
- XL4.4 Biochemistry and Molecular Biology
- XL4.5 Cell Biology
- XL4.6 Gene Expression in Eukaryotes
- XL4.7 Animal Anatomy and Physiology
- XL4.8 Parasitology and Immunology
- XL4.9 Developmental Biology
- XL4.10 Ecology
- XL4.11 Animal Behaviour
- XL5.1 Food Chemistry and Nutrition
- XL5.2 Food Microbiology
- XL5.3 Food Products Technology
- XL5.4 Food Engineering
For the full list of topics under each section, see the official GATE 2027 XL syllabus (PDF, IIT Madras) and the official question paper pattern.
Which sections to choose
Pick the two sections closest to what you studied in your degree. Before you decide, see what past papers actually tested inside Biochemistry, Botany and Zoology:
Our free notes, such as DNA Replication and Prokaryotic Gene Regulation, cover topics from XL1 Biochemistry and XL4 Zoology.
