Class 12 Biology Important Diagrams for CBSE Boards (Chapter-wise)

Class 12 Biology answers often call for a labelled diagram, and many questions are built around one. Practise these standard NCERT diagrams. Check them against the current syllabus.

Reproduction

• Transverse section (TS) of an anther; a microsporangium
• Structure of a typical anatropous ovule; the embryo sac
• Male and female human reproductive systems
• Sectional view of a seminiferous tubule; structure of a sperm
• Sectional view of the ovary
• Spermatogenesis and oogenesis (flow diagrams)

Genetics and molecular biology

• DNA double helix
• Replication fork
• A transcription unit
• The lac operon
• Pedigree charts and Punnett squares

Human health

• Structure of an antibody molecule
• Life cycle of Plasmodium

Biotechnology

• A cloning vector (for example, pBR322) and the steps of recombinant DNA technology

Ecology

• Ecological pyramids (number, biomass, energy)

Drawing tips

1. Draw large and in pencil.
2. Label with straight, non-crossing lines.
3. Add a title below the diagram.
4. For flow diagrams, keep each step on its own line with arrows.