Explain Dihybrid cross in pea plant - 5 marks
Answers
Answer:
Dihybrid cross is a cross between two different lines/genes that differ in two observed traits. According to Mendel's statement, between the alleles of both these loci there is a relationship of completely dominant - recessive traits. In the example pictured to the right, RRYY/rryy parents result in F1 offspring that are heterozygous for both R and Y (RrYy).
In this Dihybrid Cross, homozygous dominant traits were crossed with homozygous recessive traits. This particular cross always results in the phenotypic ratio of 1:0:0:0 meaning that the offspring will all have both dominant phenotypes but will be carriers of the recessive phenotypes.
In the name "Dihybrid cross", the "di" indicates that there are two traits involved (e.g. R and Y), the "hybrid" means that each trait has two different alleles (e.g. R and r, or Y and y), and "cross" means that there are two individuals (usually a mother and father) who are combining or "crossing" their genetic information.
Answer :
In a dihybrid cross, the parents carry different pair of alleles for each trait. One parent carries homozygous dominant allele, while the other one carries homozygous recessive allele. The offsprings produced after the crosses in the F1 generation are all heterozygous for specific traits.