When two independent pure lines AAbb and aaBB of pea with white flowers are crossed, the F1 progeny has purple flowers. Gene A and B link at 20 map unit. The following conclusions were made

A. When an heterozygous individual of the genotype AaBb is test crossed, progenies with purple and white in a ratio of 1:3

B. When an heterozygous individual of the genotype AaBb is test crossed, progenies with purple and white in a ratio of 1:9

C. This is an example of complementary gene action

D. The F2 progeny obtained on selfing shows both pruple and white flower in a ratio of 9:7                                            

Which of the following conclusions are correct?

#Question id: 15155

#Unit 8. Inheritance Biology

In this problem we will explore some of the many ways that mutations in two different genes can interact to produce different Mendelian ratios. Consider a hypothetical insect species that has red eyes. Imagine mutations in two different unlinked genes that can, in certain combinations, block the formation of red eye pigment yielding mutants with white eyes. In principle, there are two different possible arrangements for two biochemical steps responsible for the formation of red eye pigment. The two genes might act in series such that a mutation in either gene would block the formation of red pigment. Alternatively, the two genes could act in parallel such that mutations in both genes would be required to block the formation of red pigment.

Further complexity arises from the possibility that mutations in either gene that lead to a block in enzymatic activity could be either dominant or recessive. If the crosses between a wild type insect with red eyes and a true breeding white eyed strain with mutations in both genes. Such considerations yield the Pathways in parallel with dominant mutations in both genes, determine the phenotype of the F1 progeny and the expected phenotypic ratio of red to white eyed insects in the F2.

#Question id: 12723

#Unit 6. System Physiology – Plant

#Question id: 778

#Unit 1. Molecules and their Interaction Relevant to Biology

Inactive miRNA undergoes how many cleavages before incorporation into the RISC complex?

#Question id: 23650

#General Aptitude

#Question id: 9220

#Unit 9. Diversity of Life Forms

Which of the following factors could cause the largest increase in the effective population size of a species?