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Starch synthesis in the pea seed is cont...

Starch synthesis in the pea seed is controlled by one gene. It has two alleles B and b. If starch grain size is considered as the phenotype, then from this angle allele show

A

Multiple allele

B

Incomplete Dominance

C

Co-dominance

D

Polygenic inheritance

Text Solution

Verified by Experts

The correct Answer is:
B
• Occasionally, a single gene product may produce more than one effect.
• For example, starch synthesis in pea seeds is controlled by one gene. It has two alleles (B and b).
• Starch is synthesised effectively by BB homozygotes and therefore, large starch grains are produced.
• In contrast, bb homozygotes have lesser efficiency in starch synthesis and produce smaller starch grains.
• After maturation of the seeds, BB seeds are round and the bb seeds are wrinkled.
• Heterozygotes produce round seeds, and so B seems to be the dominant allele.
• But, the starch grains produced are of intermediate size in Bb seeds.
• So if starch grain size is considered as the phenotype, then from this angle, the alleles show incomplete dominance.
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