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GATE-Microbiology (XL- S Life Sciences) Exam Pattern

Exam Pattern

Graduate Aptitude Test in Engineering (GATE) -Microbiology (XL- S Life Sciences) has 3 hours duration.

  • The question paper will consist of both Multiple choice questions (MCQ) and Numerical answer type (NAT) questions.

  • In all the papers, there will be a total of 65 questions carrying 100 marks, out of which 10 questions carrying a total of 15 marks will be on General Aptitude (GA).

  • In the papers bearing the codes Microbiology (XL- S Life Sciences), Chemistry will carry, around 25% of the total marks, the General Aptitude section will carry 15% of the total marks and the remaining 60% of the total marks is devoted to the subject of the paper.

GATE would contain questions of two different types in various papers:

  • Multiple Choice Questions (MCQ) carrying 1 or 2 marks each in all papers and sections. These questions are objective in nature, and each will have a choice of four answers, out of which the candidate has to mark the correct answer(s).
  • Numerical Answer Questions of 1 or 2 marks each in all papers and sections. For these questions the answer is a real number, to be entered by the candidate using the virtual keypad. No choices will be shown for this type of questions. The answer can be a number such as 10 (an integer only).
  • General Aptitude (GA) Questions
    • In all papers, GA questions carry a total of 15 marks. The GA section includes 5 questions carrying 1-mark each (sub-total 5 marks) and 5 questions carrying 2-marks each (sub-total 10 marks).
  • Question Papers
  • These papers would contain 25 questions carrying 1-mark each (sub- total 25 marks) and 30 questions carrying 2-marks each (sub-total 60 marks). The question paper will consist of questions of multiple choice and numerical answer type.

A candidate appearing in the Microbiology (XL- S Life Sciences) paper has to answer the following

  • Section – Chemistry
  • GA – General Aptitude
  • Any two of XL sections Q to U

The choice of two sections from Q to U can be made during the examination after viewing the questions. Only two optional sections can be answered at a time. A candidate wishing to change midway of the examination to another optional section must first choose to deselect one of the previously chosen optional sections (Q to U).

XL Paper

In XL paper, Chemistry section is compulsory. This section contains 15 questions carrying a total of 25 marks: 5 questions carrying 1-mark each (sub-total 5 marks) and 10 questions carrying 2-marks each (sub-total 20 marks). Some questions may be of numerical answer type. Each of the other sections of the XL paper (Sections Q through U) contains 20 questions carrying a total of 30 marks: 10 questions carrying 1-mark each (sub-total 10 marks) and 10 questions carrying 2-marks each (sub-total 20 marks). Some questions may be of numerical answer type.


Chemistry (Compulsory)


Code  (P)









Food Technology





Paper General Aptitude (GA) Questions  Subject Marks     Total Marks Total Time
Microbiology (XL- S Life Sciences) 15  25+2*30 100 3 hours 

Test duration- 3 hours 

Total Marks- 15+25+2*30= 100

Total Question- 65

Marking System –

  • For 1-mark multiple-choice questions, 1/3 mark will be deducted for a wrong answer.
  • Likewise, for 2-mark multiple-choice questions, 2/3 mark will be deducted for a wrong answer.
  • There is NO negative marking for numerical answer type questions.

Syllabus Summary

No. Of Subject 12
No. Of Unit 14
No. Of Chapter 82
  1. Effect Of Physical And Chemical Agents
  2. Evaluation Of Effectiveness Of Antimicrobial Agents
  1. Microbial Interactions
  2. Carbon, Sulphur And Nitrogen Cycles
  3. Soil Microorganisms Associated With Vascular Plants
  1. Bacteria, Archea And Their Broad Classification
  2. Eukaryotic Microbes
  3. Viruses And Their Classification
  4. Molecular Approaches To Microbial Taxonomy
  1. Redox Reactions And Electron Carriers
  2. An Overview Of Metabolism
  3. Glycolysis
  4. Pentose-Phosphate Pathway
  5. Entner-Doudoroff Pathway
  6. Glyoxalate Pathway
  7. The Citric Acid Cycle
  8. Fermentation
  9. Aerobic And Anaerobic Respiration
  10. Chemolithotrophy
  11. Photosynthesis
  12. Calvin Cycle
  13. Biosynthetic Pathway For Fatty Acids Synthesis
  14. Common Regulatory Mechanisms
  15. Regulation Of Major Metabolic Pathways
  1. Cell Walls, Cell Membranes
  2. Mechanisms Of Solute Transport
  3. Flagella And Pili, Capsules
  4. Cell Inclusions
  1. Endoplasmic Reticulum
  2. Golgi Apparatus, Mitochondria And Chloroplasts
  1. Definition Of Growth
  2. Growth Curve
  3. Mathematical Expression Of Exponential Growth Phase
  4. Measurement Of Growth And Growth Yields
  5. Synchronous Growth
  6. Continuous Culture
  7. Effect Of Environmental Factors On Growth
  1. Pure Culture Techniques
  2. Theory And Practice Of Sterilization
  3. Principles Of Microbial Nutrition
  4. Enrichment Culture Techniques
  5. Light-, Phase Contrast- And Electron-Microscopy
  1. General Characteristics Of Antimicrobial Drugs
  2. Antibiotics
  3. Antifungal And Antiviral Drugs
  1. Types Of Mutation
  2. Uv And Chemical Mutagens
  3. Selection Of Mutants
  4. Ames Test For Mutagenesis
  5. Bacterial Genetic System
  6. Dna Repair
  7. Regulation Of Gene Expression
  8. Operon Model
  9. Bacterial Genome
  10. Phage Lambda and Its Life Cycle
  1. Discovery Of Microbial World
  2. Landmark Discoveries Relevant To Microbiology
  3. Controversy Over Spontaneous Generation
  4. Role Of Microorganisms In Transformation
  1. Numerical computation
  2. Numerical Estimation
  3. Numerical Reasoning
  4. Data Interpretation
  1. English grammar
  2. Sentence Completion
  3. Verbal Analogies
  4. Word Groups
  5. Instructions
  6. Critical Reasoning
  7. Verbal Deduction
  1. Normal Microbiota
  2. Classification Of Infectious Diseases
  3. Reservoirs Of Infection
  4. Nosocomial Infection
  5. Emerging Infectious Diseases
  6. Mechanism Of Microbial Pathogenicity
  7. Nonspecific Defense Of Host
  8. Antigens And Antibodies
  9. Humoral And Cell Mediated Immunity
  10. Vaccines
  11. Immune Deficiency
  12. Human Diseases

How to prepare

Preparation Strategy

Make a proper Time Table

It is very important that you make a time table and stick to it and you will have an exact idea of what you are required to study and the time required for it.

Concept clarity rather than rote learning

It is essential that you have a clear idea of the formulas and concepts rather than rote learning of things for the papers. While you might require it for memorizing formulas it is important that for other stuff you make sure you clear your basis and concepts before moving on.

Prepare Notes

It is very important make small notes or a comprehensive list of formulas on each covered topic and chapter which will come in handy at the time of revision. This will require you to be regular with your work but will surely make things easy at the time of revision.

Seek guidance

It is not possible for you to know everything in your syllabus, at least not at the time of preparation. Sooner or later you will run into a concept or so which will give you trouble and then it is best you seek guidance from an instructor or a teacher. It is necessary that you clear your doubts at regular intervals and don’t prolong things for long. Getting into a good coaching class is nothing to be ashamed off and if anything a regular coaching class will enable you to avoid roadblocks in your preparation.

Sample Papers

Even though there may be a complete change in the exam pattern or the expected questions altogether,it is important that you practice on the sample and previous years question papers available for the engineering exam you’d be attempting. You will know the existing pattern and have a fair idea of the type of questions to expect in the paper along with the time constraint.

Mock tests

The paper pattern, duration of the paper and the number of questions to be attempted in the given amount of time is not something you will be able to pick up on the day of the examination. A Mock Test tests a student’s abilities as it not only provides a similar feel of real exams but also helps in building speed and confident to face the exam. Furthermore, they can improve their performance to get an extra edge in actual exams. Try to build up an Engineering Entrance Exam Test Prep MCQ Question Bank

Time management

Time management can be learnt through thorough practice and regular test taking. So it is important that you practice it and practice it well.

Negative marking

Most the entrance examinations will have negative marking and everyone would suggest you stay clear of questions are not sure about. But some experts are of the opinion that you answer the questions in which you are confused between an option or two because there will also be a chance of getting it right.

Duration : 3 Hours

Important Instructions

Filling in Application Online 1. GOAPS: GATE Online Application Processing System (GOAPS website) has the web address It can also be accessed from the website of the respective Zonal GATE Offices or from the website of the GATE 2016 Organizing Institute. 2. Registration: A candidate must first register by providing a valid email address, mobile number and a GOAPS password. All communications from the GATE Offices will be sent to this email address (ONLY ONE PERSON CAN REGISTER WITH ONE e-mail ADDRESS). Give your personal mobile number because most of the communications may also be sent via SMS. GOAPS Password: The candidate chooses a password during Enrollment at GOAPS. This password must be remembered along with the GOAPS Enrolment ID to login to GOAPS. It is strongly encouraged to choose a password that cannot be guessed easily (it should not be the candidate’s name, date of birth, or some easily guessable string of numbers or letters like 12345 or abcd). 3. GOAPS Enrollment ID: Upon registration, an email containing the GOAPS Enrolment ID will be sent to the candidate. 4. Data Requirement for Application Filling: The following data will be required while filling the form at GOAPS. a) Personal information (name, date of birth, your personal mobile number, parents’ name, parents’ mobile number, etc.). b) Address for Communication (including PIN code), c) Eligibility degree details 13 d) College address, PIN code of college, e) GATE paper, choice of GATE examination cities, f) High quality image of your photograph conforming to the requirements specified in along with what type of photograph is accepted . g) Good quality image of your signature conforming to the requirements specified in h) Scanned copy of Degree Certificate or Certificate from Principal/HODs in pdf format. i) Scanned copy of Category/PwD Certificate (if applicable) in pdf format. j) Details of a valid ID Proof that you will carry to the examination hall. k) Your net-banking details. 5. Application Filling: The GOAPS allows you to enter data, “Save” partially filled form, “Logout”, and resume filling in by logging in again. The GOAPS portal is self-explanatory and user-friendly. Online help about using GOAPS is also available. 6. Before you make the payment, you will be shown a “Preview” of your application, where you have to carefully check for any errors. 7. Once you press “Confirm and Final Submit” button, no further changes to the application can be made by you. 8. For online payment follow the instructions given in Section for payment options. 9. Problems in Login into GOAPS –In case of forgotten user ID or password, follow instructions on the GOPAS portal to retrieve them.