Class 12 Biology questions with answers

195 NCERT Class 12 Biology questions with answers, chapter by chapter, from Sexual Reproduction in Flowering Plants to Biodiversity and Conservation.

How to teach Class 12 Biology · Class 12 Biology common misconceptions

• Chapter 1: Sexual Reproduction in Flowering Plants

  15 questions · Flower as the reproductive structure of angiosperms · Ovule, megasporogenesis, and female gametophyte · Agents of pollination and floral adaptations · Anther, microsporogenesis, and male gametophyte · Modes of pollination and outbreeding devices · Pollen-pistil interaction and controlled hybridisation · Double fertilisation, syngamy, and triple fusion · Endosperm and embryo development · Seeds, fruits, dormancy, and germination · Apomixis, polyembryony, and hybrid-seed value

• Chapter 2: Human Reproduction

  15 questions · Male reproductive system and sperm transport · Female reproductive system and mammary glands · Spermatogenesis and sperm structure · Menstrual cycle and hormonal coordination · Oogenesis, follicular growth, and ovulation · Cleavage, blastocyst formation, and implantation · Fertilisation and prevention of polyspermy · Pregnancy, placenta, and embryonic development · Parturition and neuroendocrine control · Lactation and colostrum

• Chapter 3: Reproductive Health

  15 questions · Reproductive health, education, and public-health strategy · Population growth and stabilisation · Natural contraceptive methods · Barrier methods and intrauterine devices · Hormonal and emergency contraception · Surgical contraception · Medical termination of pregnancy · Sexually transmitted infections · Assisted reproductive technologies · Infertility and clinical evaluation

• Chapter 4: Principles of Inheritance and Variation

  15 questions · Law of segregation and test crosses · Mendelian experiments, monohybrid crosses, and dominance · Incomplete dominance, codominance, and multiple alleles · Dihybrid crosses and independent assortment · Chromosomal theory, linkage, and recombination · Polygenic inheritance and pleiotropy · Sex determination systems · Mutation and mutagens · Pedigree analysis and Mendelian disorders · Chromosomal disorders and nondisjunction

• Chapter 5: Molecular Basis of Inheritance

  15 questions · DNA and RNA polynucleotide structure · DNA packaging in prokaryotes and eukaryotes · Experimental identification of genetic material and RNA world · Semiconservative DNA replication · Transcription units and RNA processing · Genetic code and coding mutations · tRNA, ribosomes, and translation · Regulation of gene expression and lac operon · Human Genome Project and genome features · DNA fingerprinting and VNTR polymorphism

• Chapter 6: Evolution

  15 questions · Major transitions in the history of life · Origin of life and chemical evolution · Evidence from fossils, homology and analogy · Adaptive radiation and convergent evolution · Darwinian natural selection and fitness · Evolutionary forces and modes of selection · Natural selection observed in real time · Mutation, variation and speciation · Hardy-Weinberg genetic equilibrium · Origin and evolution of humans

• Chapter 7: Human Health and Disease

  15 questions · Common bacterial and viral infections · Health, disease and host factors · Malaria and vector-borne disease · Innate immunity and barriers · Acquired humoral and cell-mediated immunity · Vaccination and passive immunity · Allergy and autoimmunity · HIV infection and AIDS · Cancer, detection and treatment · Drug and alcohol dependence

• Chapter 8: Microbes in Human Welfare

  15 questions · Microbes in household food production · Industrial fermentation products · Antibiotics and responsible use · Activated sludge and anaerobic digestion · Methanogens and renewable energy · Microbial biocontrol · Primary and secondary sewage treatment · Scaling microbial welfare processes · Biofertilisers and nitrogen fixation · Mycorrhiza and plant benefit

• Chapter 9: Biotechnology Principles and Processes

  15 questions · Core principles of biotechnology · Gel electrophoresis and elution · Restriction enzymes and recognition sites · Cloning-vector architecture · Competent hosts and DNA uptake · DNA isolation and controlled cutting · Polymerase chain reaction · Bioreactor design and control · Downstream processing and quality · Ligation, transformation and screening

• Chapter 10: Biotechnology and Its Applications

  15 questions · Bt crops and insect specificity · GM agriculture: benefits and limits · RNA interference · Recombinant human insulin · Gene therapy for ADA deficiency · Molecular diagnosis · Transgenic animals · Biosafety and ethical evaluation · Biopatents and biopiracy · Recombinant therapeutics and vaccines

• Chapter 11: Organisms and Populations

  15 questions · Exponential and logistic growth · Organisms and abiotic environment · Adaptations to deserts and extremes · Density dependence and population regulation · Population attributes · Life-history strategies · Competition and predation · Parasitism and host relations · Mutualism and commensalism · Regulation, conformity, migration and suspension

• Chapter 12: Ecosystem

  15 questions · Ecosystem structure and components · Carbon cycle · Primary productivity · Decomposition process and controls · Food chains and food webs · Ecological pyramids · Energy flow and transfer efficiency · Ecological succession · Phosphorus cycle · Ecosystem services

• Chapter 13: Biodiversity and Conservation

  15 questions · Biodiversity, productivity and stability · Latitudinal and species-area patterns · Levels of biodiversity · Extinction rates and the current crisis · Habitat loss and fragmentation · Overexploitation, invasions and coextinction · Ex-situ conservation · In-situ conservation and hotspots · Conservation decisions and global cooperation · Sacred groves and community stewardship