The prescribed syllabus by CBSE is expected to:

  • Promote understanding of basic principles of Biology;
  • Encourage learning of emerging knowledge and its relevance to individual and society;
  • Promote rational/scientific attitude towards issues related to population, environment and development;
  • Enhance awareness about environmental issues, problems and their appropriate solutions;
  • Create awareness amongst the learners about diversity in the living organisms and developing respect for other living beings;
  • Appreciate that the most complex biological phenomena are built on essentially simple processes.

Course Structure (2017-18)

Class-XII      (Theory)

Unit Title No. Of Periods Marks
VI Reproduction 30 14
VII Genetics and Evolution 40 18
VIII Biology and Human Welfare 30 14
IX Biotechnology and its Applications 30 10
X Ecology and Environment 30 14
  Total 160 70

Unit-VI: Reproduction (30 periods)

Chapter-1: Reproduction in Organisms

Reproduction, a characteristic feature of all organisms for continuation of species; modes of reproduction – asexual and sexual reproduction; asexual reproduction – binary fission, sporulation, budding, gemmule formation, fragmentation; vegetative propagation in plants.

Chapter-2: Sexual Reproduction in Flowering Plants

Flower structure; development of male and female gametophytes; pollination – types, agencies and examples; outbreeding devices; pollen-pistil interaction; double fertilization; post fertilization events – development of endosperm and embryo, development of seed and formation of fruit; special modes-apomixis, parthenocarpy, polyembryony; Significance of seed dispersal and fruit formation.

Chapter-3: Human Reproduction

Male and female reproductive systems; microscopic anatomy of testis and ovary; gametogenesis – spermatogenesis and oogenesis; menstrual cycle; fertilisation, embryo development upto blastocyst formation, implantation; pregnancy and placenta formation (elementary idea); parturition (elementary idea); lactation (elementary idea).

Chapter-4: Reproductive Health

Need for reproductive health and prevention of Sexually Transmitted Diseases (STDs); birth control – need and methods, contraception and medical termination of pregnancy (MTP); amniocentesis; infertility and assisted reproductive technologies – IVF, ZIFT, GIFT (elementary idea for general awareness).

Unit-VII: Genetics and Evolution (40 Periods)

Chapter-5: Principles of Inheritance and Variation

Heredity and variation: Mendelian inheritance; deviations from Mendelism – incomplete
dominance, co-dominance, multiple alleles and inheritance of blood groups, pleiotropy;
elementary idea of polygenic inheritance; chromosome theory of inheritance; chromosomes and genes; Sex determination – in humans, birds and honey bee; linkage and crossing over; sex linked inheritance – haemophilia, colour blindness; Mendelian disorders in humans – thalassemia; chromosomal disorders in humans; Down’s syndrome, Turner’s and Klinefelter’s syndromes.

Chapter-6: Molecular Basis of Inheritance

Search for genetic material and DNA as genetic material; Structure of DNA and RNA; DNA packaging; DNA replication; Central dogma; transcription, genetic code, translation; gene expression and regulation – lac operon; genome and human and rice genome projects; DNA fingerprinting.

Chapter-7: Evolution

Origin of life; biological evolution and evidences for biological evolution (paleontology,
comparative anatomy, embryology and molecular evidences); Darwin’s contribution, modern synthetic theory of evolution; mechanism of evolution – variation (mutation and recombination) and natural selection with examples, types of natural selection; Gene flow and genetic drift; Hardy – Weinberg’s principle; adaptive radiation; human evolution.

Unit-VIII: Biology and Human Welfare  (30 Periods)

Chapter-8: Human Health and Diseases

Pathogens; parasites causing human diseases (malaria, dengue, chickengunia, filariasis, ascariasis, typhoid, pneumonia, common cold, amoebiasis, ring worm) and their control; Basic concepts of immunology – vaccines; cancer, HIV and AIDS; Adolescence – drug and alcohol abuse.

Chapter-9: Strategies for Enhancement in Food Production

Improvement in food production: Plant breeding, tissue culture, Biofortification, Apiculture and Animal husbandry.

Chapter-10: Microbes in Human Welfare

In household food processing, industrial production, sewage treatment, energy generation and microbes as biocontrol agents and biofertilizers. Antibiotics; production and judicious use.

Unit-IX: Biotechnology and Its Applications (30 Periods)

Chapter-11: Biotechnology – Principles and processes

Genetic Engineering (Recombinant DNA Technology).

Chapter-12: Biotechnology and its Application

Application of biotechnology in health and agriculture: Human insulin and vaccine production, stem cell technology, gene therapy; genetically modified organisms – Bt crops; transgenic animals; biosafety issues, bio piracy and patents.

Unit-X: Ecology and Environment (30 Periods)

Chapter-13: Organisms and Populations

Organisms and environment: Habitat and niche, population and ecological adaptations; population interactions – mutualism, competition, predation, parasitism; population attributes – growth, birth rate and death rate, age distribution.

Chapter-14: Ecosystem

Ecosystems: Patterns, components; productivity and decomposition; energy flow; pyramids of number, biomass, energy; nutrient cycles (carbon and phosphorous); ecological succession; ecological services – carbon fixation, pollination, seed dispersal, oxygen release (in brief).

Chapter-15: Biodiversity and its Conservation

Concept of biodiversity; patterns of biodiversity; importance of biodiversity; loss of biodiversity; biodiversity conservation; hotspots, endangered organisms, extinction, Red Data Book, biosphere reserves, national parks, sanctuaries and Ramsar sites.

Chapter-16: Environmental Issues

Air pollution and its control; water pollution and its control; agrochemicals and their effects; solid waste management; radioactive waste management; greenhouse effect and climate change; ozone layer depletion; deforestation; any one case study as success story addressing environmental issue(s).

Practicals

Evaluation Scheme Marks
One Major Experiment Part A (Expt. No. 5, 6, 8, 9) 5
One Minor Experiment Part A (Expt. No. 2, 3, 4) 4
Slide Preparation Part A (Expt No. 1, 7) 5
Spotting Part B 7
Practical Record + Viva Voce 4
Project Record + Viva Voce 5
Total 30

A. List of Experiments

  1. Study pollen germination on a slide.
  2. Collect and study soil from at least two different sites and study them for texture, moisture content, pH and water holding capacity. Correlate with the kinds of plants found in them.
  3. Collect water from two different water bodies around you and study them for pH, clarity and presence of any living organism.
  4. Study the presence of suspended particulate matter in air at two widely different sites.
  5. Study the plant population density by quadrat method.
  6. Study the plant population frequency by quadrat method.
  7. Prepare a temporary mount of onion root tip to study mitosis.
  8. Study the effect of different temperatures and three different pH on the activity of salivary amylase on starch.
  9. Isolate DNA from available plant material such as spinach, green pea seeds, papaya, etc.

B. Study/observation of the following (spotting)

  1. Flowers adapted to pollination by different agencies (wind, insects, birds).
  2. Pollen germination on stigma through a permanent slide.
  3. Identification of stages of gamete development, i.e., T.S. of testis and T.S. of ovary through permanent slides (from grasshopper/mice).
  4. Meiosis in onion bud cell or grasshopper testis through permanent slides.
  5. T.S. of blastula through permanent slides (Mammalian).
  6. Mendelian inheritance using seeds of different colour/sizes of any plant.
  7. Prepared pedigree charts of any one of the genetic traits such as rolling of tongue, blood groups, ear lobes, widow’s peak and colour blindness.
  8. Controlled pollination – emasculation, tagging and bagging.
  9. Common disease causing organisms like Ascaris, Entamoeba, Plasmodium, Roundworm through permanent slides or specimens. Comment on symptoms of diseases that they cause.
  10. Two plants and two animals (models/virtual images) found in xeric conditions. Comment upon their morphological adaptations.
  11. Two plants and two animals (models/virtual images) found in aquatic conditions. Comment upon their morphological adaptations.

Prescribed Books:

  1. Biology Class-XII, Published by NCERT
  2. Other related books and manuals brought out by NCERT (consider multimedia also)

Reference Materials:

  1. Online Labs (http://www.olabs.edu.in/?pg=topMenu&id=53) for practicals related videos.