Bihar Board Class 12 Biology Syllabus
Bihar Board Class 12 Biology Syllabus

Bihar School Examination Board (BSEB) has prepared a detailed syllabus for Class 12 Biology exam of 2021-22. The syllabus is comprehensive and has been designed in such a manner that it helps students to prepare for both board exams as well as medical entrance exams. In this writeup, we will cover the detailed Bihar Board Biology class 12 syllabus 2021-22, the evaluation pattern of the board, the significance of each chapter, key takeaways from those chapters, and some important FAQs.

The new syllabus aims to help students become better in understanding the concepts given in the curriculum of Biology. It is a must that students study and analyze the syllabus before they start studying the subject. Apart from the theoretical portion of 70 marks, the subject has a 30 mark practical paper which consists of various experiments and practical work. Read the article till the end to learn about the experiments you need to carry out as a part of the Bihar board biology class 12 syllabus 2021-22.


Theory Syllabus of Bihar Board Class 12 Biology



  Chapter name






Genetics and evolution



Biology and human welfare



Biotechnology and its applications



Ecology and environment







The syllabus for Class 12th Biology consists of 5 units and 16 chapters in total. Each unit carries varying marks in the exam based on its importance. The unit genetics and evolutions carry the most marks in all as it is considered the most crucial part than other units.

Moreover, other units such as reproduction, biology and human welfare and ecology and environment have been allocated 14 marks each and ranks second among the highest weightage. This, in no way, means that the fourth unit, which consists of two chapters, is not important. The table also shows the increasing importance of biotechnology and its applications. For your reference, the names of all the chapters is given below:

Unit I: Reproduction

  • Chapter 1 — Reproduction in organisms


  • Chapter 2 — Sexual reproduction in flowering plants


  • Chapter 3 — Human reproduction


  • Chapter 4 — Reproductive health

Unit II: Genetics and evolution

  • Chapter 5 — Principles of inheritance and variation


  • Chapter 6 — Molecular basis of inheritance


  • Chapter 7 — Evolution

Unit III: Biology and human welfare

  • Chapter 8 — Human health and diseases


  • Chapter 9 — Strategies for enhancement in food production


  • Chapter 10 — Microbes in human welfare


Unit IV: Biotechnology and its applications

  • Chapter 11 — Biotechnology: Principles and Processes


  • Chapter 12 — Biotechnology and its applications


Unit V: Ecology

  • Chapter 13 — Organisms and Population


  • Chapter 14 — Ecosystems


  • Chapter 15 — Biodiversity and it’s Conservation


  • Chapter 16 — Environmental issues


So students should keep their focus on the units carrying the highest weightage and the chapters included therein. However, they must not neglect the other chapters as there may be some surprise questions from them.




Practical Syllabus of Bihar Board Class 12 Biology 


Apart from theory, class 12 Biology also has a practical paper as well. The revised syllabus of practical has two parts. The first part deals with the external evaluation, while the other is the internal evaluation. Students are awarded marks in a combined manner by both the evaluations. Their subject teacher will allot 50% marks as an internal evaluator and the remaining 50% by an external evaluator.

External Evaluation

S. no.




Slide preparation






Sessional work submission and oral

2+2= 4






There are two experiments that students need to conduct as a part of external evaluation.

Slide Preparation

In the first experiment of external evaluation, students are required to prepare a slide on anyone from the following: 

  1. Study pollen germination on a slide.
  2. To study mitosis, construct a temporary mount of the onion root tip.


Observe/study the following:

  1. Flowers become pollinated by different agents (like wind, insects).
  2. Recognizing the stages of gamete development, i.e., T.S. of testis and T.S. of ovary through permanent slides with the help of grasshopper/mice.
  3. With the help of permanent slides, conduct meiosis in onion bud cells or grasshopper testis.


  1. Transverse sections(T.S) of blastula with the use of permanent slides(Mammalian).


  1. Work on pedigree charts of any genetic trait such as tongue rolling, blood groups, ear lobes, widow’s peak, and color blindness.
  2. Observe organisms like Ascaris, Entamoeba, any fungus causing ringworm, and Plasmodium, responsible for commonly caused diseases through permanent slides or specimens. Also, mention the symptoms of conditions that they cause.


  1. Models/virtual images of Two animals and two plants were found in xeric conditions. Give your views upon their morphological adaptations.
  2. Models/virtual images of two plants and two animals found in aquatic conditions and give your views upon their morphological adaptations.

Note: Please note the above given list of experiments is indicative in nature. Students are advised to contact their school exam department for further information on practical exam.

Internal Evaluation

S. no.




One major experiment



One minor experiment



Project work + oral





You must complete and submit a project and viva or oral exam as part of the Internal Evaluation process. Please note that project work and viva carry six marks.

One Major Experiment

You are required to perform a significant experiment from the following:

  1. Study the effect of different temperatures and three different pH on the activity of salivary amylase on starch.
  2. Isolate DNA from available plant material such as spinach, green pea seeds, papaya, etc.

One Minor Experiment

You are required to perform a minor experiment from the following:

  1. Collect and study soil from at least two sites for texture, moisture content, pH, and water holding capacity. Correlate with the kinds of plants found in them.
  2. Collect water from two different water bodies around you and study them for pH, clarity and the presence of any living organism.

NotePlease note the above given list of experiments is indicative in nature. Students are advised to contact their school exam department for further information on practical exam.


FAQs for Bihar Board Class 12 Biology Subject:


Q1. How should I prepare for the BSEB Class 12 Biology Exam?


Ans. Students must be familiar with the exam syllabus, question paper pattern, and they should focus on crucial areas (refer to important questions, sample papers to get an idea), and stick to a study schedule to prepare for the exam.


Q2. Will the syllabus be reduced for the academic session 2021-22 as well?

Ans: Keeping in mind the Covid-19 restrictions, the BSEB had reduced the syllabus for all the subjects by 25% for the year 2020-21 for the convenience of students. However, no such announcement has been made for the academic session 2021-22. Students are advised to keep visiting the official website of the BSEB –  to stay updated.


Q3. From where should students prepare for Class 12 Biology Exam?

Ans: Students can solve the Class 12 questions from their Bihar Board state text books. They can also go through the last ten years’ question papers to familiarize themselves with the entire coursework. 


Q4. Why is it critical to know the exam’s syllabus ahead of time?

Ans. Knowing the syllabus ahead of time allows students to have a better understanding of the topics, leading to confidence during the exam. It also helps students to improve their time management skills.


Q5. Can students from the Bihar Board clear the IIT-JEE or NEET exam?

Ans. Yes, many BSEB students have achieved good results in JEE/ NEET in the past. If you prepare well for your target examination, you too can clear these prestigious competitive exams with flying colors. All the Best!


Q6. When will the practical exams be held?

Ans. The dates for internal assessment/practical exams will be declared by your school authorities. Students are advised to contact their school exam department for further information