CBSE Class 12 Biology 2020-21 – Syllabus, Question Papers, Notes, NCERT Solutions

CBSE Class 12 Biology

CBSE Class 12 Biology 2020-21: Biology is the branch of the science of life and living organisms. An organism is a living entity consisting of one cell, e.g., bacteria, or several cells, e.g., animals, plants, and fungi. The word biology is taken from the Greek words “bios” and “logos. “Bios” means life, “Logos” means study. Aspects of biological science range from the study of molecular mechanisms in cells to the classification and behavior of organisms, the Evolution of species, and interaction between ecosystems.

You should have the right study materials to prepare for CBSE Class 12 Biology Exam. Otherwise, you will lose your chance to score a better mark in the CBSE board exam.

CBSE Class 12 Biology 2020-21

Biology has great importance for CBSE Class 12 Exam for Science stream. If you have a dream to become a Physician or want to do the advance research on Human beings, plants, and other living beings, then this subject is especially for you.

You can divide the Biology into at least nine fields, again every field has its respective subfields.

  • Biochemistry: the study of the material substances that make up living things.
  • Botany: the study of plants, including agriculture.
  • Cellular biology: the study of the basic cellular units of living things.
  • Ecology: the study of how organisms interact with their environment.
  • Evolutionary biology: the study of the origins and changes in the diversity of life over time.
  • Genetics: the study of heredity.
  • Molecular biology: the study of biological molecules.
  • Physiology: the study of the functions of organisms and their parts.
  • Zoology: the study of animals, including animal behavior.

You can score high in the Class 12 Biology exam by proper preparation. Hence, it will help you to improve your overall score in the CBSE 12th board exam, Apart from that, with a thorough concept on the subject can help you to crack various exams like,

  • NEET
  • JIPMER etc.

CBSE Class 12 Biology Books 2020-21

You must have the NCERT Class 12 Biology book to prepare for the Exam. Because they are following the latest Biology CBSE Syllabus. NCERT experts have used simple and clear language so that every student can easily understand all chapters. They have also provided multiple examples when required to clear the concept of the students.

You will also find the exercise in the ending section of every chapter. By solving all questions and developing a thorough concept, you can score the better grade in the final exam. For that, you must have an NCERT Class 12 Biology book. Along with that, you can follow the books as given below as a reference,

  • Golden Biology Class XII by N K Sharma
  • Comprehensive Biology Activities Class 12th by Dr. N. K. Verma
  • Conceptual Biology For Class XII S K Jain And Shailesh K Jain
  • Moderns ABC Plus Of Biology by Dr. S. P. Jauhar

You will find the following chapters in 12th CBSE Biology for English Medium,

You will find the following chapters in 12th CBSE Biology for Hindi Medium,

Chapter 1 Reproduction in Organisms

In this chapter, you will come to know about types, modes, and the process of reproduction in different organisms. You will also learn about asexual reproduction, sexual reproduction, pre-fertilization events, fertilization, and post-fertilization events.

You will learn following sub-topics,

  • Life span: The period from birth to the natural death of an organism.
  • Reproduction:
    • The biological process through which an organism gives rise to young offspring similar to itself.
    • It enables the continuity of the species, generation after generation.
  • The process of reproduction of an organism depends on the following:
    • Organism’s habitat
    • Its internal physiology
    • Several other factors
  • Reproduction is of two types:
    • Asexual mode: Reproduction involving a single parent or without the involvement of gamete formation.
    • Sexual mode: Reproduction involving two parents (opposite sex) and also involves the fusion of male and female gametes.

Chapter 2 Sexual Reproduction in Flowering Plants

Here you will learn about the structure, morphology, and process of sexual reproduction in flowering plants. Also, the subtopics covered in this chapter include pre-fertilization events, double fertilization, post-fertilization events, and the knowledge about apomixis and polyembryony.

It is a combination of four chapters and has a weightage of fourteen marks in 12 board examinations.

Chapter 3 Human Reproduction

In this chapter, we will learn about the human male and female reproductive systems. Diagrams, illustrations, flowcharts, and easy language makes this chapter comprehensive and easy to learn. Moreover, the sequential progress of the topics helps us retain and grasp better.

The subtopics covered in this chapter are-

  • Reproductive structures,
  • Male reproductive systems,
  • Female reproductive systems,
  • The role of sex hormones,
  • Gametogenesis,
  • Spermatogenesis and more introductory topics of human reproduction.

Chapter 4 Reproductive Health

This chapter focusses on the issues of the significance of reproductive health and the methods to achieve it, also focusses on maternal health and the health of the child during pre-pregnancy, pregnancy, and post-pregnancy periods. Infant mortality maternal mortality and amniocentesis are other topics covered here.

The subtopics covered in this chapter are:

  • Reproductive Health – Problems and Strategies
  • Population Explosion and Birth Control,
  • Medical Termination of Pregnancy,
  • Sexually Transmitted Diseases.

Chapter 5 Principles of Inheritance and Variation

In this chapter, you will learn about Genetics and Evolution. You will also learn the Similarity and variation between the parents and offspring’s are discussed in this chapter.

Mendel’s law of inheritance, the inheritance of one gene, the inheritance of two genes, sex determination, mutations, and genetic disorders are the main topics discussed here. You will find the Diagrams, illustrations, flowcharts in the chapters.

Chapter 6 Molecular Basis of Inheritance

Here, you will learn about the structures of DNA, RNA, the process of replication, etc.

The topics covered in this chapter are:

  • The DNA: Structure of polynucleotide chain, Packaging of DNA helix.
  • The search for genetic material: The genetic material is DNA, Properties of genetic material.
  • RNA world.
  • Replication: The experimental proof, the machinery, and enzymes.
  • Transcription: The transcription unit, Transcription unit, and the gene, Types of RNA, and the process of transcription.
  • Genetic code: Mutations and genetic code, t RNA. Translation. Regulation of gene expression.
  • The Lac Operon.
  • Human genome project: Salient

Chapter 7 Evolution

Here you will learn about the Evolution, i.e., the study of the history of life forms on earth.

In this chapter, you will come to know about the origin of life and the Evolution of life forms or biodiversity on planet earth in the context of the Evolution of earth and against the background of the Evolution of the universe itself, also find various Diagrams, illustrations, flowcharts. It will help you to understand every topic of the chapter in the right way.

Chapter 8 Health and Diseases

Here you will study Health and diseases. It comprises maintenance of optimum health, diseases, types, treatment and prevention, immunity, and its types and address to some diseases such as AIDS, cancer, and adolescent issues constitute.

Subtopics covered in this chapter are:

  • Common Diseases in Humans
  • Immunity
  • AIDS
  • Cancer
  • Drugs and Alcohol Abuse.

Chapter 9 Strategies for Enhancement in Food Production

Here you will learn about the biological principles applied to animal husbandry and plant breeding to increase food production.

You will also find several new techniques like embryo transfer technology and tissue culture techniques for enhancing food production.

Chapter 10 Microbes in Human Welfare

Here, you will learn about Microbes. Microbes are micro-organisms or microscopic organisms seen under a microscope. These are small living creatures, invisible to the naked eye, and are present all around us, in air, water, soil, and so on. They have a great role in the Evolution of the planet earth. Among these microbes, few cause severe infections, and deadly diseases and rests are the beneficial ones and harmless to our lives.

You should know that disease-causing microbes are called pathogens. Influenza, tuberculosis, polio, cholera, HIV are some of the best examples of diseases caused by these microbes. The most common microbes include Bacteria, protozoa viroid, some algae, Fungi, and Viruses.

Chapter 11 Biotechnology Principles and Processes

In this chapter, you will learn about the principles and processes involved in biotechnology. Biotechnology is defined as” the integration of natural science and organisms, cells, parts thereof, and molecular analogs for products and services.”

Among many techniques, modern biotechnology is the result of the following two core techniques. They are-

  • Genetic engineering
  • Manufacturing of Antibiotics, Drugs and other Vaccines

Chapter 12 Biotechnology and its Application

Here you will know about the various human application of biotechnology to improve the quality of human life. Especially in the field of food production and health.

Biotechnology has given humans several useful products by using microbes, plants, animals, and their metabolic machinery.

Chapter 13 Organisms and Populations

Here you will learn about the ecology at organismic and population level. This chapter comprises topics such as organisms and its environment, niche, major abiotic factors affecting the organisms.

You will also know about the organism’s environment, such as temperature, water, light, and soil, responses to abiotic factors such as regulation, conformation, migration, and suspension.

Chapter 14 Ecosystem

Here you will learn about the Ecosystem. Ecology is the subject that studies the interactions among organisms and between the organism and its physical (abiotic) environment.

There are four levels of biological organization:

  • organisms
  • populations
  • communities
  • biomes

It can be visualized as a functional unit of nature, where living organisms interact among themselves and also with the surrounding physical environment.

In the starting section, you will learn about the structure of Ecosystem in order to appreciate the input (productivity), transfer of energy (food chain), and the output.

Chapter 15 Biodiversity and its Conservation

In this chapter, you will study about biodiversity and its importance, its types, patterns, Evolution, degradation, and conservation.
You will also learn about Genetic diversity, species diversity, latitudinal gradients, species-area relationship, causes of biodiversity losses, in-situ conservation, and ex-situ conservation.

Chapter 16 Environmental Issues

You will learn various Environmental problems because of the ecological imbalance such as pollution, global warming, deforestation, etc.

You will also learn various methodologies to control Environmental issues such as pollution. Here you can also see the effects of pollution on human life and how it is affecting the people’s day to day life.

CBSE Class 12 Biology Syllabus 2020-21

Here you will get the detailed CBSE Class 12 Syllabus 2020-21 for Biology along with section-wise marks distribution. You can take a look at the units included in CBSE 12th Biology Syllabus along with the marks distribution:








Genetics and Evolution



Biology and Human Welfare



Biotechnology and its Applications



Ecology and Environment 





CBSE Class 12 Biology Solutions 2020-21

Class 12 Biology solutions play a great role in preparing for CBSE 12th Biology exam. After the textbook, you must refer to Class 12 Biology solutions to prepare the 12th Exam correctly.

Biology Solutions will help you to build depth concept by providing the exercise wise explanation of all the problems. You will also find various Additional Questions from every exercise.

CBSE Class 12 Biology NCERT Solutions 2020-21

NCERT experts have created Class 12 Biology Solutions to provide you depth concepts on every chapter. Experts have used simple and clear language while creating solutions so that any students can understand every problem without the help of any subject experts.


You should know that NCERT solutions have followed the latest CBSE syllabus and refer them as soon as possible to start your Biology preparation. It will not only help you to build the depth concept on the subject but also help you to crack various entrance and competitive exams.

CBSE Class 12 Biology Question Paper 2020-21

You should have an idea about exam question pattern and weightage distributions for various sections before appearing for any exam and start solving various questions papers after completion of your 12th Biology chapters and exercises from previous exams to get the idea about the 12th CBSE Biology exam. It will help you to find the important sections and also help you to boost your speed by solving question papers.

You should have the following materials to find the complete question papers related to CBSE Class 12th Biology Exam,

  • Sample Question Papers
  • Previous Year Question Papers
  • Question Bank

CBSE Class 12 Biology Sample Question Papers

The  Central Board of Secondary Education (CBSE) publishes the sample papers and marking schemes yearly to give an idea about the Exam to students.


After completion of a sample paper in the certain time as the real exam, you will easily identify your preparation status. It will also get a preview of the board question paper. It will also enhance your problem-solving speed and understanding of the subject. You will become more aware of the current pattern of the question papers after solving Class 12 Sample papers.

CBSE Class 12 Biology Previous year Papers

Previous year papers are the great exam materials to prepare any exams.  You must solve the 12th previous year papers for biology before the board exam. You will recognize the changes in the previous exams throughout the time.


It will give you an idea about the repetitive sections and questions in class 12 Biology. You can also know your current preparation status by solving the previous year’s papers in the certain time as the real Exam and know preparation status and also help you to find your conceptual weaknesses. You can easily cover those before the board exam.

CBSE Class 12 Biology Question Bank 2020-21

You should have a Class 12 Biology Question Bank 2020-21 to bring your preparation to the next level.  You should note that experts have created the materials by analyzing the 12th Biology chapter-wise exercise and the previous exams. You will find multiple questions for every single topic.

You can build the depth concept in class 12 Biology by practicing more questions.

CBSE Class 12 Biology Worksheets 2020-21

Biology Worksheets are also important materials to boost your exam preparation. It will provide Biology chapter-wise various important questions based on previous exams.

In the Worksheet, we have also provided all the Class 12 Biology important questions and answers in the worksheets included in the latest CBSE NCERT Syllabus.

CBSE Class 12 Biology Revision Notes 2020-21

Without revision of the complete syllabus, you will lose your chance to score a better grade in the 12th Board exam. To make your revision easier, our experts have created Class 12 Biology Revision Notes.

Here you will find all chapter-wise theorems and concepts are summarized in the easier way so that any student can understand them quickly. They have also considered by analyzing previous years of question papers and Biology chapters. With the help of these, you can easily do proper revision before the board exam. It will help you to revise all chapters in the easier way in less time.

We have covered a detailed guide on CBSE Class 12 Biology 2020-21. Feel Free to ask any questions in the comment section below.

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