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Topic Chromosomes
Asked 3 times across 3 UPSC exams over 39 years (1984–2023), peaking in 1984.
Key insights
- Most tested in CSE — 1 of 3 PYQs
- Most asked in 1984
- Recurs across 3 years (1984–2023)
How it travelled across exams
First appearance in each exam — the same idea, reframed.
CSE 1984 → CDS 2020 → GEO 2023
How the concept evolved
Rising — more than half its appearances (2 of 3) are since 2016.
Related concepts
Ideas UPSC tests alongside this one — keep exploring.
Sample questions
You've seen the pattern — here are a few of the actual PYQs.
GEO2023
What is the number of chromosomes found in human somatic cell?
- A 48
- B 56
- C 46 ✓
- D 42
✓ Correct answer: (C)
Science & Technology › Biology & Health
CDS2020
In human beings, the chromosomes that determine birth of a normal female child are
- A one X chromosome from mother and one X chromosome from father ✓
- B one X chromosome from mother and one Y chromosome from father
- C two X chromosomes from mother and one X chromosome from father
- D one X chromosome from father and one Y chromosome from mother
✓ Correct answer: (A)
Science & Technology › Biology & Health
CSE1984
Sex of a child is determined by the
- A Chromosomes of father ✓
- B Chromosomes of mother
- C Rh factor of parents
- D None of these
✓ Correct answer: (A)
Science & Technology › Biotech & Genetics
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