CBSE +2 Biology

Class XII
One Paper Time: 3 Hours Marks : 70
Unit Marks
1. Sexual reproduction 12
2. Genetics and evolution 20
3. Biology and human Welfare 12
4. Biotechnology and its applications 12
5. Ecology and environment 14
Total 70
I SEXUAL REPRODUCTION (35 Periods)
Pollination and fertilization in flowering plants.
Development of seeds and fruits.
Human reproduction: reproductive system in male and female, menstrual cycle. Production of
gametes, fertilization, implantation, ,embryo development, pregnancy and parturation.
Reproductive health - birth control, contraception and sexually transmitted diseases.
II Genetics and evolution (45 Periods)
Mendelian inheritance.
Chromosome theory of inheritance, deviations from Mendelian ratio (gene interaction- Incomplete
dominance, co-dominance, complementary genes, multiple alleles).
Sex determination in human beings: XX, XY.
Linkage and crossing over.
Inheritance pattern of haemophilia and blood groups in human beings.
DNA: replication, transcription, translation.
Gene expression and regulation.
Genome and Human Genome Project.
DNA fingerprinting.
Evolution: Theories and evidences.III BIOLOGY AND HUMAN WELFARE (35 Periods)
Animal husbandry.
Basic concepts of immunology, vaccines.
Pathogens, Parasites.
Plant breeding, tissue culture, food production.
Microbes in household food processing, industrial production, sewage treatment and energy
generation.
Cancer and AIDS.
Adolescence and drug/alcohol abuse.
IV BIOTECHNOLOGY AND ITS APPLICATIONS (30 Periods)
Recombinant DNA technology.
Applications in Health, Agriculture and Industry
Genetically modified (GM) organisms; biosafety issues.
Insulin and Bt cotton
V ECOLOGY & ENVIRONMENT (35 Periods)
Ecosystems: components, types and energy flow.
Species, population and community.
Ecological adaptations.
Centres of diversity and conservation of biodiversity, National parks and sanctuaries.
Environmental issues.
Practicals
Time: 3 Hours 60 Periods
1. Two experiments 4+4=8 Marks
2. Slide preparation 5 Marks
3. Spotting 7 Marks
4. Investigatory project and Viva based on the project 5 Marks
5. Record and Viva based on the experiment 5 Marks
30 Marks
List of Experiments
1. Study pollen germination on a slide.
2. Collect and study soil from different sites and study them for texture and moisture
content.3. Study the pH and water holding capacity of soil. Correlate with the kinds of plants found
in them.
4. Collect water from different Water bodies around you and study them for pH, clarity and
presence of any living organisms.
5. Study the presence of suspended particulate matter in air at the two widely different sites.
6. Study of plant population density by quadrat method.
7. Study of plant population frequency by quadrat method.
8. Study of mitosis in onion root tip (preparation)
Study/observation of the following (Spotting)
1. Study of flowers adapted to pollination by different agencies (wind, insect)
2. Study of pollen germination on a slide.
3. Study and identify stages of gamete development i.e. T.S. testis and T.S. ovary through
permanent slide. (from any mammal)
4. Study meiosis in onion bud cell or grass hopper testis through permanent slide.
5. Study of t.s. of blastula through permanent slide.
6. Study Mendelian inheritance using seeds of different colour/size of any plant.
7. Study prepared pediqree charts of genetic traits such as rolling of tongue, blood groups,
widow’s peak, colour blindness.
8. Exercise on controlled pollination-Emasculation, tagging and bagging.
9. To identify common diseases causing organism like Ascaris, Entamoeba, Plasmodium,
ringworm. Comment on symptoms of diseases that they cause through permanent slides
or specimens.
10. Study plants and animals found in xerophytic condition. Comment upon their adaptation/
ecosystem.
11. Study plants and animals found in aquatic conditions. Comment upon their adaptation/
ecosystem.
12. Study analogous and homologous organs in various plants and animals.