Write the phenotype for the genotype BB, Bb, with respect to starch synthesis in a pea seed
Answers
Answer:
The starch synthesis in pea plants is controlled by a single gene. It has two alleles B and b. BB homozygotes produced large starch grains as compared to that produced by bb homozygotes. After maturation it was observed that BB seeds were round and bb were wrinkled. When they were crossed the resultant progeny were intermediate-sized Bb seeds. The cross involved is
B
B
b
Bb
Bb
b
Bb
Bb
Deviation from Mendel's law of dominance: If starch grain size is considered as the phenotype, then from this angle, the alleles show incomplete dominance. Thus, dominance is not an autonomous feature of a gene, it depends on gene product and production of particular phenotype from this product.
Answer:
Pleiotropy is a condition in which single genes affects many characters or single gene effects many phenotypes for example synthesis in pea is controlled by one gene and that gene is also responsible for the shape of the seed.
So, the correct option is 'Both Assertion and Reason are correct and Reason is not the correct explanation for Assertion'.