Home › Tamil Nadu SSLC (Class 10) › Biology › Genetics › In a dihybrid cross, the 9 : 3 : 3 : 1 phenotypi…
In a dihybrid cross, the 9 : 3 : 3 : 1 phenotypic ratio of the F2 generation is a direct demonstration of which of Mendel's laws?
ALaw of independent assortment
BLaw of dominance of factors
CLaw of segregation of factors
DLaw of recapitulation theory
Answer & Solution
Correct answer: A. Law of independent assortment
1. A dihybrid cross follows two pairs of traits, such as seed shape and seed colour, at once.
2. The appearance of new combinations like round-green and wrinkled-yellow shows the two trait pairs are inherited independently.
3. This independence is the law of independent assortment, option A.
4. The law of segregation explains the 1:2:1 of a single gene, not the four-way 9:3:3:1, which rules out option C.
_Source: Samacheer Kalvi (TN SCERT) Class 10 Science, Unit 18 Genetics "Mendel's Laws", p.271_
Related questions
Plants used in Mendel's first-generation crosses were labelled the generation called:The probability of an event found by dividing occurrences by opportunities is described asA recessive disorder preventing proper metabolism of phenylalanine and tyrosine is:Ignoring seed colour, the share of a dihybrid F2 generation with round seeds is:In pea plants round seed shape is dominant over shape that is:The F2 phenotypic ratio from a standard dihybrid cross is:A cross between true-breeding parents differing in two characteristics is a:The rule that genes do not influence each other's sorting into gametes is the law of indep