The West Bengal Board has released the latest curriculum and syllabus for the class 12 students. This article will provide you with the free PDF link to download the Biological Science syllabus. Biological science, also known as biology, is the study of life and living organisms. It encompasses a vast array of disciplines that explore the structure, function, growth, evolution, distribution, and taxonomy of living organisms. The subject consists of 100 marks, theory and project work. Check out the complete article for the WB Board class 12 Math curriculum and syllabus for the academic year 2024-24.
The WBCHSE class 12 Biological Science syllabus has been released. The syllabus for the academic year 2024-25 has been provided here with the PDF link. The subject consists of a theory part of 70 marks and project work 30, all total of 100 marks. The link is provided to download the complete syllabus and curriculum along with the practical work in PDF format, click the links which has been mentioned below in the article:
DownloadWBCHSE Biology Syllabus 2026 PDF Here
Unitwise Marks Distribution from 2025-26 Syllabus
Below given is the detailed marks distribution:
Unit Name | Marks |
Unit I: Reproduction Organisms | 14 |
Unit II: Genetics and Evolution* | 18 |
Unit III: Biology and Human Welfare | 14 |
Unit IV: Biotechnology | 10 |
Unit V: Ecology and Environment* | 14 |
WBCHSE Class 12 Biology Syllabus 2025-26
Below given is the details of the syllabus:
Unit | Topics | Contact Hours | Marks |
UNIT VI REPRODUCTION | Chapter 1: Sexual Reproduction in flowering plants Flower structure;Development of male and female Gametophytes; Pollination — Types, Agencies and examples; Out breeding 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; Seed dispersal and fruit formation and their significance. | 15 | 33 |
Chapter 2: Human reproduction Male and female reproductive systems; Anatomy and Histology of testis and ovary, Gametogenesis-Spermatogenesis and Oogenesis; Menstrual cycle; Fertilization,embryo development up to blastocyst, formation and implantation; Pregnancy and placenta formation and function;Parturition: mechanism and neuroendocrine system involved in this mechanism, Lactation. | 15 | ||
Chapter 3: 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). | 3 | ||
UNIT-VII (GENETICS AND EVOLUTION) | Chapter 4: Principles of Inheritance and Variation. Heredity and Variation: Mendelian inheritance, Deviations from Mendelism-Incomplete dominance, Codominance, 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 honeybees; Linkage and crossing over; Sex linked inheritance hemophilia,colour blindness; Mendelian disorders in humansThalassemia; Pedigree Analysis; chromosomal disorders in humans; Down’s syndrome, Turner’s syndrome and Klinefelter’s syndrome. | 20 | 57 |
Chapter 5: Molecular basis of inheritance Search for genetic material and DNA as genetic material(experiments on bacterial transformation by F. Griffith; Avery, MacLeod and McCarty; Experiment by Hershey and Chase; Structure of DNA and RNA, DNA packaging, DNA replication; Central Dogma; Genetic Code, Translation, gene expression and regulation-lac operon; Genome, Human and Rice genome projects; DNA fingerprinting. | 25 | ||
Chapter 6: Evolution Origin of life;Biological evolution and evidences for biological evolution(Palaeontology, Embryology and molecular evidence); Darwin's contribution, modern synthetic theory; Mechanism of evolution – Variation (Mutation and Recombination) and Natural selection with examples, types of natural selection; Gene flow and genetic drift; Hardy-Weinberg Principle; Adaptive radiation; Human evolution. | 12 |
