Same chapter1 markDifficulty: Easy
The phenotypic ratio of the F2 generation of a monohybrid cross is:
Genetics
2 marksDifficulty: Easy
Explain why the father, and not the mother, determines the sex of a human child.
Original Khojo Papers practice question — not from a past board paper.
Answer
The mother produces only X-bearing eggs, while the father produces both X-bearing and Y-bearing sperms. If an X-bearing sperm fertilises the egg the child is a girl (XX); if a Y-bearing sperm does so the child is a boy (XY). The sex therefore depends on the sperm.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The human female is homogametic (XX) and the male is heterogametic (XY).
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Same chapter2 marksDifficulty: Easy
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State Mendel's law of segregation.
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Same chapter3 marksDifficulty: Medium
Explain sex determination in human beings.
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Same chapter4 marksDifficulty: Medium
In pea plants tall (T) is dominant over dwarf (t). A pure tall plant is crossed with a dwarf plant. Give the genotype and phenotype of the F1 and the F2 generations.
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Same chapter3 marksDifficulty: Medium
State Mendel's law of independent assortment and name the cross that demonstrates it.
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