Class 12 Biology: Principles of Inheritance and Variation

Answer key included

This worksheet tests your understanding of fundamental concepts in inheritance and variation, including Mendelian genetics, incomplete dominance, codominance, and genetic disorders.

Class 12CBSEBiologymedium

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Class 12 · Biology
Name: ____________
  1. Q1.Which of the following is an example of incomplete dominance?
    • A.ABO blood groups in humans
    • B.Flower color in Mirabilis jalapa (4 o'clock plant)
    • C.Coat color in cattle (Roan)
    • D.Sickle cell anaemia
  2. Q2.If a dihybrid cross is performed between two heterozygous individuals (AaBb x AaBb), what will be the phenotypic ratio in the F2 generation?
    • A.3:1
    • B.9:3:3:1
    • C.1:2:1
    • D.1:1
  3. Q3.The phenotypic expression of all the genes present in an individual is called its ____.
  4. Q4.Turner’s syndrome is caused by the loss of a ____ chromosome.
    • A.single autosome
    • B.single X
    • C.single Y
    • D.pair of autosomes

Preview — full sheet in the PDF

What's inside this workbook

This Class 12 Biology Practice contains 10 questions across 2 printable pages and includes a full answer key at medium difficulty. Aligned to the CBSE and NCERT syllabus.

How this worksheet helps your child

  • Builds confidence in core Biology concepts taught in Class 12 through repeated, varied practice.
  • Aligned to CBSE and NCERT — questions mirror the pattern children see in school tests and unit assessments.
  • Comes with an answer key so parents and students can self-check in minutes, without needing a teacher.
  • Pitched at medium level — use it for daily homework, weekend revision or quick exam warm-ups.

Topics covered

geneticsinheritancevariationmendelcbserevisionbiology

How to use this worksheet at home

Open the print view and use your browser's Print dialog to print on regular A4 paper or save as a PDF. Hand the printed sheet to your child (Class 12) and set a relaxed time limit — 15 to 25 minutes works for most Biology worksheets. When they're done, open the "With answer key" view and let them self-mark question by question. Re-print as many times as you need; the file never expires and there's no download limit.

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Does it include an answer key?
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