Current Affairs updated daily
KalviGavaniKalviGavani
Class 12 · Tamil Nadu State Board

Tamil Nadu Class 12 Biology Term 2 Unit Test — Samacheer Kalvi

Class 12 Biology Term 2 practice test for Tamil Nadu State Board students with questions from inheritance, molecular genetics, evolution, health, and biotechnology.

Updated 17 May 20262 min read

Instructions

  • Time: 45 minutes
  • Total marks: 30
  • Use comparison tables where suitable.

Portion Covered

  • Principles of Inheritance and Variation
  • Molecular Genetics
  • Evolution
  • Human Health and Diseases
  • Microbes in Human Welfare
  • Applications of Biotechnology

Section A — One Mark Each

1. Define gene. 2. What is phenotype? 3. Name the base present in RNA instead of thymine. 4. What is a codon? 5. Define evolution. 6. Name one evidence for evolution. 7. What is vaccination? 8. Name one useful product obtained from microbes. 9. Expand PCR. 10. Which organs indicate divergent evolution?

Section B — Two Marks Each

1. Distinguish between genotype and phenotype. 2. Write any two features of genetic code. 3. Distinguish between homologous and analogous organs. 4. State any two methods of disease prevention. 5. Write any two applications of biotechnology.

Section C — Five Marks Each

1. Explain Mendel's monohybrid cross. 2. Explain transcription and translation. 3. Explain Hardy-Weinberg principle and factors disturbing equilibrium.

Answer-Writing Guide

  • Keep genetics ratios exact.
  • In molecular genetics, preserve sequence and direction.
  • For evolution, pair every term with one clear explanation.
  • Use tables for all comparison questions.

Self-Review Checklist

  • [ ] I wrote ratios correctly.
  • [ ] I used DNA/RNA terms accurately.
  • [ ] I explained natural selection clearly.
  • [ ] I used exact vocabulary in long answers.
  • [ ] I corrected every weak answer after review.
← Browse all Class 12 Exercise Solutions

More exercise solutions