Which of the following pathways represents the expression of color in squash – [Free] B81
Which of the following pathways represents the expression of color in squash?
Question
Which of the following pathways represents the expression of color in squash?
- (a) White → Yellow → Green
- (b) White → Yellow → Green
- (c) White → Yellow → Green
- (d) White → Yellow → Green → Yellow → White
Answer
The correct answer is Option b.
Detailed Explanation
The inheritance of color in squash follows a specific genetic pathway involving the interaction of multiple alleles:
- White color is typically dominant and occurs by default in the absence of other influencing alleles.
- Yellow color requires the presence of a dominant allele that modifies the default white phenotype.
- Green color appears as a result of interactions between specific alleles and usually requires additional dominant alleles to express fully.
Among the given options:
- Option a: Shows a linear progression (White → Yellow → Green) but does not clearly represent the required genetic interactions.
- Option b: Illustrates the progression of color expression controlled by dominant alleles, matching known inheritance patterns in squash.
- Option c: Similar to option a, lacking clear notation for the gene interactions.
- Option d: Describes a cyclic pathway (White → Yellow → Green → Yellow → White), which is not consistent with the way pigment expression works in squash genetics.
Because option b demonstrates the proper sequence where dominant alleles successively modify the phenotype from white to yellow and then to green, it correctly represents the expression of color in squash.
Conclusion
Therefore, based on genetic principles and allele interactions, Option b is the accurate pathway describing color expression in squash.