CBSE Class 12

Biology

13 units · 105 topicsInternal 30Exam 70

Prep tip

Half the marks test knowledge and understanding; the rest test applying and analysing. Practise the labelled diagrams (flower, embryo sac, testis, ovary, the replication fork, the lac operon, pBR322), genetic crosses with ratios, and the steps of recombinant DNA technology.

Suggested order: Unit I, then II, then III, then IV, then V, then VI, then VII, then VIII, then IX, then X, then XI, then XII, and XIII last.

Units

Unit I0 of 9 read

Sexual reproduction in flowering plants

9 sheets · about 87 min reading

Flower structure: stamen, anther, pistil and ovule9 min Microsporogenesis and the pollen grain (male gametophyte)10 min Megasporogenesis and the embryo sac (female gametophyte)10 min Pollination: types, agencies and examples11 min Outbreeding devices, pollen-pistil interaction and artificial hybridisation11 min Double fertilisation8 min Post-fertilisation: development of endosperm and embryo10 min Seed and fruit formation, and why they matter10 min Special modes: apomixis, parthenocarpy and polyembryony8 min

Unit II0 of 7 read

Human reproduction

7 sheets · about 72 min reading

Male reproductive system and the T.S. of testis10 min Female reproductive system and the mammary gland10 min Spermatogenesis, its hormonal control and the sperm10 min Oogenesis and the T.S. of ovary11 min The menstrual cycle11 min Fertilisation, embryo development up to the blastocyst, and implantation10 min Pregnancy, placenta, parturition and lactation10 min

Unit III0 of 6 read

Reproductive health

6 sheets · about 52 min reading

Reproductive health: need, problems and strategies8 min Sexually transmitted diseases (STDs) and their prevention8 min Population stabilisation and birth control: the need7 min Methods of contraception12 min Medical termination of pregnancy (MTP) and amniocentesis8 min Infertility and assisted reproductive technologies (ART)9 min

Unit IV0 of 9 read

Principles of inheritance and variation

9 sheets · about 94 min reading

Mendel's monohybrid cross: dominance and segregation12 min Dihybrid cross and the law of independent assortment11 min Incomplete dominance, co-dominance and ABO blood groups11 min Pleiotropy and polygenic inheritance8 min Chromosome theory of inheritance, linkage and crossing over11 min Sex determination in humans, birds and honey bee9 min Sex-linked inheritance and pedigree analysis12 min Mendelian disorders: sickle-cell anaemia, phenylketonuria and thalassemia11 min Chromosomal disorders: Down's, Turner's and Klinefelter's syndromes9 min

Unit V0 of 9 read

Molecular basis of inheritance

9 sheets · about 99 min reading

The search for the genetic material: DNA is the genetic material11 min Structure of DNA and RNA, and DNA packaging12 min DNA replication: semiconservative copying12 min Central dogma and transcription12 min The genetic code, mutations and tRNA11 min Translation: making the polypeptide10 min Regulation of gene expression: the lac operon11 min The Human Genome Project and the rice genome10 min DNA fingerprinting10 min

Unit VI0 of 9 read

Evolution

9 sheets · about 83 min reading

Origin of life10 min Evidences for evolution: fossils, embryos and molecules9 min Comparative anatomy: homologous and analogous organs9 min Darwin's contribution and natural selection11 min Types of natural selection7 min Mechanism of evolution: mutation, recombination, gene flow and drift10 min Hardy-Weinberg principle11 min Adaptive radiation7 min Origin and evolution of humans9 min

Unit VII0 of 9 read

Human health and diseases

9 sheets · about 93 min reading

Pathogens; typhoid, pneumonia and common cold9 min Malaria, dengue and chikungunya11 min Filariasis, ascariasis, amoebiasis, ringworm and disease control11 min Immunity: innate and acquired; antibodies and immune responses12 min Active and passive immunity; vaccination and immunisation9 min Allergies, autoimmunity and the lymphoid organs10 min Cancer: causes, detection and treatment10 min HIV and AIDS10 min Adolescence: drug and alcohol abuse11 min

Unit VIII0 of 7 read

Microbes in human welfare

7 sheets · about 58 min reading

Microbes in food processing8 min Microbes in industrial production9 min Microbes in sewage treatment10 min Microbes in energy generation: biogas8 min Microbes as biocontrol agents8 min Microbes as biofertilisers7 min Antibiotics: production and judicious use8 min

Unit IX0 of 8 read

Biotechnology: principles and processes

8 sheets · about 79 min reading

Principles of biotechnology9 min Restriction enzymes: the molecular scissors10 min Cloning vectors and pBR32212 min Competent host and inserting recombinant DNA8 min Isolating DNA, with the plant DNA practical10 min Cutting DNA and gel electrophoresis10 min Amplifying a gene: PCR10 min Getting the product: bioreactors and downstream processing10 min

Unit X0 of 9 read

Biotechnology and its applications

9 sheets · about 82 min reading

Biotechnology in agriculture and health: an overview8 min Bt crops: pest resistance with Bt toxin10 min Pest-resistant plants by RNA interference9 min Human insulin by recombinant DNA technology9 min Vaccine production and stem cell technology9 min Gene therapy: the ADA deficiency case9 min Molecular diagnosis: PCR, probes and ELISA10 min Transgenic animals9 min Biosafety, biopiracy and patents9 min

Unit XI0 of 8 read

Organisms and populations

8 sheets · about 76 min reading

Populations and population density10 min Population attributes: birth rate, death rate, sex ratio and age pyramids9 min Population growth: what changes population density7 min Growth models: exponential and logistic growth, and life history variation12 min Population interactions: predation9 min Population interactions: competition9 min Population interactions: parasitism9 min Population interactions: commensalism, mutualism and amensalism11 min

Unit XII0 of 7 read

Ecosystem

7 sheets · about 60 min reading

Ecosystem: patterns and components9 min Productivity: GPP, NPP and secondary productivity8 min Decomposition9 min Energy flow in an ecosystem9 min Food chains, food webs and trophic levels8 min Ecological pyramids: pyramids of number and biomass9 min Pyramid of energy and the limits of ecological pyramids8 min

Unit XIII0 of 8 read

Biodiversity and its conservation

8 sheets · about 72 min reading

Biodiversity: concept and levels9 min Patterns of biodiversity: latitudinal gradients and species-area relationships11 min Importance of biodiversity: stability and why we conserve it9 min Loss of biodiversity and the evil quartet10 min Endangered organisms, extinction and the Red Data Book8 min Biodiversity conservation: in situ, ex situ and hotspots10 min Protected areas: biosphere reserves, national parks and wildlife sanctuaries8 min Sacred groves and Ramsar sites7 min

How the 100 marks split

Internal · Major experiment5

Internal · Minor experiment4

Internal · Slide preparation5

Internal · Spotting7

Internal · Practical record and viva4

Internal · Investigatory project and viva5

End-semester exam70

Total100

The usual internal split. Your college may differ.Practise a model paper