NCERT Solutions For Class 12 Biology - 2026-27

Class 12 Biology becomes easier to prepare when you study each chapter, practise the NCERT questions, and review your answers along the way. Vedantu’s NCERT Solutions for Class 12 Biology provide clear chapter-wise explanations to help you understand textbook questions, clear doubts, and revise important concepts. 

You can access the NCERT Biology Class 12 Solutions PDF for each chapter and use them for regular practice and CBSE exam preparation. 

These Class 12 Biology chapter-wise solutions also help you check your approach while solving Biology Class 12 questions and answers. Explore the CBSE Class 12 Biology Solutions chapter-wise below.

Chapter 1: Sexual Reproduction in Flowering Plants

This chapter focuses on the sexual reproduction in flowering plants along with the structure, morphology, and processes, including pollination,  seed development, and fruit formation. It further elaborates on concepts like pre-fertilization: Structure and Events, Port fertilization: Structure and Events, Double fertilization, Polyembryony, and Apomixis.

This chapter is very important for Class 12 Boards as it holds a substantial weightage. The important topics that are covered in NCERT Class 12 Biology Chapter 1 are:

• Sexual reproduction in flowering plants

• Structure and morphology of flowering plants

• Pre-fertilization, double fertilization, and post-fertilization events in flowering plants

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Chapter 2: Human Reproduction

In the Human Reproduction chapter, the reproductive events in humans are discussed. This includes gametogenesis (the formation of gametes). Humans become sexually mature after reaching puberty. The reproductive events related to males and females are different. You will be able to examine these differences in this chapter. The sub-topics discussed in this chapter include the female reproductive system, the male reproductive system, fertilization and implantation, menstrual cycle, gametogenesis, embryonic development and pregnancy, lactation, and parturition.

This chapter is important for the Class 12 examination and explains the human reproduction system with diagrams and illustrations in a detailed manner. The important topics from NCERT Class 12 Chapter 2 Biology  are:

• Reproductive structures

• Male and female reproductive systems

• Role of sex hormones

• Spermatogenesis

• Gametogenesis

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Chapter 3: Reproductive Health

The previous chapters covered the human reproductive system as well as its functions. In this chapter, a closely related topic is discussed - Reproductive Health. Reproductive health refers to the healthy reproductive organs and their normal functions. The World Health Organization (WHO) defines reproductive health as the total well-being in every aspect of reproduction which includes physical, behavioral, social, and emotional. This chapter will cover subtopics like Reproductive Health - Problems and Strategies, Birth Control, Population Explosion, Medical Termination of Pregnancy, Infertility, Sexually Transmitted Diseases, etc.

The important topics covered under this chapter that are important for Class 12 boards are as follows:

• Significance of reproductive health

• Infant mortality 

• Maternal mortality

• Amniocentesis

• Sexually Transmitted Diseases

• Population Explosion and birth control

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Chapter 4: Principles of Inheritance and Variation

Genetics is one of the many branches of Biology. It deals with inheritance and the variance of characters in offspring from their parents. The inheritance process involves the characters passed on from the parents to their progeny. In this chapter, concepts like Mendel’s different Laws of Inheritance, Sex Determination, Inheritance of One Gene or Two Genes, Genetic Disorders, and Mutation are discussed in detail.

Through this chapter, students will be able to understand the concept of genetics and evolution. It will teach you sex determination by chromosomes and how parental traits are inherited by their offspring. The important topics covered under NCERT Class 12 Biology Chapter 4 are:

• Mendel’s law of inheritance

• Inheritance of one gene

• Inheritance of two genes

• Mutations

• Genetic disorders 

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Chapter 5: Molecular Basis of Inheritance

The previous chapters have covered the inheritance patterns as well as the genetic basis of these patterns. During the time of Mendel, the factors that regulated the inheritance pattern were unclear. However, over the next century, the investigation of the nature of putative genetic material saw great strides. It led to the realization that Deoxyribonucleic Acid (DNA) is the genetic material for most organisms. Class XI syllabus covered that nucleic acids were polymers of nucleotides. This chapter will cover concepts like the DNA, RNA World, Search for Genetic Materia, Genetic Code, Transcription, Replication, Translation, Human Genome Project, DNA Fingerprinting, and Regulation of Gene Expression.

The important topics covered under NCERT Class 12 Chapter 5 are as follows:

• Structure of DNA and polynucleotide chain

• Packaging of DNA helix

• Properties of DNA

• RNA 

• Types of RNA

• Regulation of gene expression

• Process of replication, transcription, and translation

• Human genome project

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Chapter 6: Evolution

Evolution explores the history and gradual development of life on Earth. This chapter covers important concepts such as the origin of life, evidence for evolution, adaptive radiation, mechanisms of evolution, biological evolution, the Hardy-Weinberg principle, and the origin and evolution of humans. Understanding these concepts helps build a clear foundation for answering questions related to evolutionary processes.

The important topics covered in this chapter are as follows:

• Origin of life

• Evolution of life forms

• Biodiversity on Earth

• Hardy Weinberg Principle

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Chapter 7: Human Health and Diseases

NCERT Class 12 Biology Chapter 7 will help the students to know about some common diseases in humans and their prevention. 

Health can be Affected by:

• Genetic Disorders - Conditions with which a child is born or defects or deficiencies they inherit from their parents.

• Infections.

• Lifestyle - Habits that we have, water and food that we consume, exercise and rest that we take.

This chapter will explore topics like Common Diseases in Humans, Drugs, Cancer, AIDS, Alcohol Abuse, and Immunity.

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Chapter 8: Microbes in Human Welfare

Apart from macroscopic animals and plants, biological systems have another major component known as microbes. In previous classes, students learned about living organisms and their diversity. Microbes are a diverse group that include bacteria, protozoa, fungi, and microscopic plant and animal viruses. Microbes like many fungi and bacteria can grow on nutritive media and form colonies that are visible to the naked eye. These cultures are very useful while studying microorganisms. In this chapter, topics like Microbes in Industrial Products, Microbes in Household Products, Microbes in Biogas Production, Microbes in Sewage Treatment, Microbes as Biofertilizers, and Microbes in Biocontrol Agents are explained thoroughly.

NCERT Class 12 Biology Chapter 8 is important to learn about various diseases which are caused by microbes. Along with this, the chapter also focuses on some of the microbes which are harmless and beneficial to humans.

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Chapter 9: Biotechnology Principles and Processes

Biotechnology is a field that deals with the process of using enzymes from organisms or live organisms for producing processes and products that are useful to humans. According to the definition provided by the European Federation of Biotechnology (EFB), biotechnology encompasses traditional views as well as modern molecular biotechnology. It is the integration of organisms, cells, and molecular analogues and natural science for services and products. This chapter will cover concepts like Principles of Biotechnology, Recombinant DNA Technology tools and processes, etc.

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Chapter 10: Biotechnology and Its Application

In the previous chapters, there were concepts covering the industrial-scale production of biologicals and biopharmaceuticals using genetically modified animals, plants, fungi, and microbes. This chapter covers the applications of biotechnology, including diagnostics, therapeutics, genetically modified crops used for agriculture, waste treatment, energy production, bioremediation, and processed food. It also includes concepts like Biotechnical Applications in Medicine and Agriculture, Transgenic Animals, Ethical Issues, etc.

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Chapter 11: Organisms and Populations

The previous chapters have covered that Ecology involves studying how organisms interact with one another, other organisms, and the physical environment. This chapter involves discussions on biological organization’s four levels - organisms, populations, biomes, and communities. The Ecology at the population and organismic levels are explained in detail. It also includes concepts like Organisms and their Environment and Populations.

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Chapter 12: Ecosystem

An Ecosystem can be considered as nature's functional unit where organisms live and interact with each other as well as the surrounding physical environment. The Ecosystem chapter will begin with discussing the ecosystem structure. This will help in understanding the input, transfer of energy, and output. Next comes the relationships that are created because of the energy flows in the system and the inter-relationship, including webs, chains, and cycles. The chapter covers subtopics like Structure and Function of Ecosystem, Decomposition, productivity, Energy Flow, Ecological Succession, Ecological Pyramids, Ecosystem Services, and Nutrient Cycling.

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Chapter 13: Biodiversity and Conservation

The Biodiversity and Conservation chapter covers topics like Species diversity, Genetic diversity, Ecological Diversity, Patterns of Diversity, Loss of Biodiversity, Different types of Species, Biodiversity Conservation, etc. The conservation of Biodiversity might be in situ or ex-situ. In the case of situ conservation, the species that are endangered receive protection in their natural habitat in order to ensure the protection of the entire ecosystem. In ex-situ conservation, the threatened species are protected in botanical gardens and zoological parks through cryopreservation of gametes, tissue culture propagation, and in vitro fertilization.

The important topics covered in this chapter are:

• Importance and significance of biodiversity

• Types of Biodiversity

• Evolution, degradation, and conservation

• Genetic diversity

• Species diversity

• Latitudinal gradients

• Species area relationship

• Causes of biodiversity losses

• In-situ conservation and ex-situ conservation

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CBSE Class 12 Biology Syllabus Course Structure 2026-27

CBSE Class 12 Biology NCERT Solutions 2026-27 - Benefits of NCERT Solutions

CBSE Class 12 Biology NCERT Solutions have its own advantages when it comes to preparing the students of CBSE Class 12 Biology:

• It Is useful for quick revision of all the chapters before exams.

• It gives an in-depth understanding of complex topics covered in the syllabus.

• It helps to achieve good grades in exams.

• The solutions are designed by experts as per the CBSE latest guidelines.

• They are available online on Vedantu’s official website free of cost.

CBSE Class 12 Biology NCERT Solutions 2026-27 - Extra Questions for Practice 

1. What is Sponge’s asexual reproductive structure?

2. Monohybrid cross involves independent assortment. True or false?

3. What is the difference between the Menstrual cycle and the Oestrus cycle?

4. Explain the following:

1. Scutellum

2. Apomixis

5. What is the development process for microspores in angiosperms?

6. What is the hormone that women produce during pregnancy?

7. What is the difference between incomplete dominance and codominance?

8. Name the scientist who rediscovered Mendel’s laws.

9. What will happen when YyRr is crossed with a wrinkled pea plant? Explain with a diagram.

10. What is mutagen? Explain using an example.

11. What is MTP?

12. Define menarche.

13. Draw a diagram of the seminiferous tubule and label it.

14. Which fallopian tube’s part is closest to the ovary?

15. After fertilisation, what happens to Synergids?

16. Draw anatropous ovule and label its parts.

17. What is the difference between geitonogamy, autogamy, and xenogamy?

18. What do we call the gamete mother cells present in diploid organisms?

19. What is the cross-pollination process in plants?

Related Important Links for CBSE Class 12 Biology

NCERT Class 12 Biology Solutions are available for free access, helping students work through textbook questions, clear doubts, and strengthen their understanding of important concepts. The detailed Class 12 Biology NCERT Solutions also support thorough chapter-wise revision and exam preparation.