Download (Updated) CBSE Class 12 Biology Syllabus 2020-21: Reduced 30%

The new and updated CBSE class 12 syllabus (2020-21) is out. The 30% reduction from the entire CBSE Class 12 biology syllabus this year. For preparation for the upcoming CBSE biology exam for class 12, students can download the latest and updated CBSE class 12 biology syllabus 2020-21. From this article, students will also get the revised CBSE class 12 biology marking scheme, deleted topics, preparation tips, and many more. 

VSI provides a reduced CBSE class 12 biology syllabus and practical syllabus for biology with the evaluation scheme in a pdf format for students to download for free. To clear the upcoming CBSE biology board exam with flying colors, students are advised to minutely go through the Class 12 Biology syllabus 2020-21.

For all new updates regarding the CBSE class 12 Syllabus 2020-21, students can bookmark this page. 


Download PDF of CBSE Class 12 Biology Syllabus 2020-21: Reduced by 30%

Class 12 students preparing for CBSE Board exam 2020-21,  must refer to the CBSE class 12 biology syllabus 2020-21 given below. Also, students must download CBSE class 12 biology syllabus pdf for future reference for free from this page. This year, because of the pandemic, the class 12 biology syllabus 2020-21 has been reduced by 30%. Therefore, students are advised to download the revised CBSE 12 biology syllabus from the given link below. 


Revised CBSE Class 12 Biology Syllabus (2020-21)Click Here

Unit-VI Reproduction

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; fertilization, embryo development up to 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

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 human being, birds, and honey bee; linkage and crossing over; sex-linked inheritance – hemophilia, color 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, Human and rice genome projects; DNA fingerprinting. 

Unit-VIII Biology and Human Welfare

Chapter-8: Human Health and Diseases

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

Chapter-10: Microbes in Human Welfare

Microbes in food processing, industrial production, sewage treatment, energy generation, and microbes as biocontrol agents and bio-fertilizers. Antibiotics; production and judicious use. 

Unit-IX Biotechnology and its Applications

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, biopiracy, and patents. 

Unit-X Ecology and Environment

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-15: Biodiversity and its Conservation

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

CBSE Class 12 Biology Syllabus 2020-21: Deleted Topics 

Under Unit-VI Reproduction

Chapter-1: Reproduction in Organism

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.  

Under Unit-VII Genetics and Evolution

Chapter-7: Evolution

Origin of life; biological evolution and evidence for biological evolution (paleontology, comparative anatomy, embryology, and molecular evidence); Darwin’s contribution, the 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.  Under Unit-VIII Biology and Human Welfare

Chapter 9: Strategies for Enhancement in Food Production

Animal husbandry, Plant breeding, tissue culture, single-cell protein.  

Under Unit-X Ecology and Environment

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 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 impact and mitigation; ozone layer depletion; deforestation; exemplifying case study as a success story addressing the environmental issue(s).

CBSE Class 12 Biology Marking Scheme 2020-21: Revised

VIIGenetics and Evolution18
VIIIBiology and Human Welfare14
IXBiotechnology and its Applications12
XEcology and Environment12

Download PDF of CBSE Class 12 Practical Biology Syllabus 2020-21: Reduced by 30%

The CBSE class 12 practical syllabus for Biology 2020-21 is also reduced by 30%. Students before preparing for the upcoming exam must go through the class 12 practical biology syllabus 2020-21 thoroughly. Download the CBSE class 12 practical biology syllabus 2020-21 from the given PDF link below. 

Download Class 12 Practical Biology Syllabus for CBSE (2020-21)Click Here 

1. List of Experiments

a. Prepare a temporary mount to observe pollen germination.

b. 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.

c. Collect water from two different water bodies around you and study them for pH, clarity, and presence of any living organism.

d. Prepare a temporary mount of the onion root tip to study mitosis.

e. Study the effect of different temperatures or three different pH on the activity of salivary amylase on starch.

f. Isolate DNA from available plant material such as spinach, green pea seeds, papaya, etc.

2. Study/observation of the following (Spotting)

a. Flowers adapted to pollination by different agencies (wind, insects, birds).

b. Identification of stages of gamete development, i.e., T.S. of testis and T.S. of ovary through permanent slides (from grasshopper/mice).

c. Meiosis in onion bud cells or grasshopper testis through permanent slides.

d. T.S. of blastula through permanent slides (Mammalian).

e. Prepared pedigree charts of any one of the genetic traits such as rolling of tongue, blood groups, ear lobes, widow’s peak, and color blindness.

f. Common disease-causing organisms like Ascaris, Entamoeba, Plasmodium, any fungus causing ringworm through permanent slides, models, or virtual images. Comment on symptoms of diseases that they cause.

g. Two plants and two animals (models/virtual images) found in xeric conditions. Comment upon their morphological adaptations.

h. Two plants and two animals (models/virtual images) found in aquatic conditions. Comment upon their morphological adaptations.

CBSE Class 12 Biology Practical Syllabus 2020-21: Deleted Topics 

1. List of Experiments

a. Study the presence of suspended particulate matter in the air at two widely different sites.

b. Study the plant population density by quadrat method.

c. Study the plant population frequency by quadrat method.

2. Study/Observer of the following (spotting)

a. Pollen germination on stigma through a permanent slide or scanning electron micrograph.

b. Mendelian inheritance using seeds of different colors/sizes of any plant.

c. Controlled pollination – emasculation, tagging, and bagging.

CBSE Class 12 Biology Practical Marking Scheme 2020-21: Revised

Marking SchemeMarks
One Major Experiment 5, 65
One Minor Experiment 2, 34
Slide Preparation 1, 45
Practical Record + Viva VoceCredit to the students’ work over the academic session may be given4
Investigatory Project and its project
and its Record + Viva Voce

CBSE Class 12 Biology Examination 2020-21: Preparation Tips

To score good marks for CBSE class 12 Biology Examination 2020-21 students must follow the given preparation tips.

  1. For the preparation for the upcoming exam, students have to complete the CBSE Class 12 Biology syllabus and practical syllabus 2020-21.
  2. Students must learn the theory and practice diagram very well. 
  3. Class 12 Students should cover the entire CBSE Class 12 Biology syllabus. 
  4. To stay focused throughout the preparation students must eat healthily and exercise yoga daily. 
  5. Once the completion of the Chemistry syllabus, students must solve the CBSE class 12 Biology sample papers.

After the completion of class 12, students can go for various career endeavors. Students can also opt for CA preparation after class 12th. The dream of becoming a CA can easily be accomplished if students join the best CA institute “VSI Jaipur”. This place offers its students the best education with an outstanding faculty. 

Frequently Asked Questions

Q1. What are the changes made by the Board in the CBSE class 12 biology Syllabus 2020-21?

Ans: The board has reduced the CBSE class 12 Biology syllabus 2020-21 by 30%. The Revised CBSE class 12 biology syllabus 2020-21 is provided on this page for students to download. 

Q2. What portions have been removed from the CBSE class 12 Biology Syllabus 2020-21?

Ans: The deleted topics from the CBSE class 12 biology syllabus 2020-21 are mentioned above on this page. 

Q3. What books are recommended for CBSE class 12 Biology Exam 2020-21?

Ans: The students must prepare from NCERT books for the preparation of CBSE class 12 biology exam 2020-21. NCERT books have detailed explanations of every topic and the language used in the book is easily understandable. 

Q4. How to prepare for the CBSE class 12 Biology Exam 2020-21?

Ans: To prepare for the CBSE class 12 Biology exam 2020-21, preparation tips are mentioned above on this page. For the CBSE class 12 board exam preparation 2020-21 for the rest of the subjects click on the given link.