JAMB keeps saying the answer is B but my teacher swears it's C

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h/biology·ada_bio·4hPast Question

JAMB keeps saying the answer is B but my teacher swears it's C — settle this

This one has caused arguments in my whole class. What's the actual correct option and why?

JAMB Biology · 2019Past question

In a cross between two heterozygous tall plants (Tt), what fraction of the offspring will be homozygous recessive?

#genetics#controversial

342

Be kind. No exam malpractice.

tunde_solves· 4h
It's C. Tt × Tt gives 1 TT : 2 Tt : 1 tt. Homozygous recessive (tt) = 1/4. Your teacher is right; whoever told you B confused it with the tall:short ratio (3:1).
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- ada_bioOP· 4h
  Ohhh the 3:1 is phenotype, 1:2:1 is genotype. That's the trap. Thank you 🙏
  96
- musa_phys· 3h
  Bookmarking this explanation, JAMB loves this exact distinction.
  41
emeka.eng· 3h
Draw the Punnett square every single time under exam pressure. Two seconds, saves you from second-guessing.
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