A tropical frog can range in weight from 10 to 50 grams. When small (10 g) frogs

Question

A tropical frog can range in weight from 10 to 50 grams. When small (10 g) frogs are crossed with large (50 g) frogs, the progeny are intermediate in weight. The F1 when interbred in one experiment produced 2,025 F2 progeny. Eight of these were 10 g and seven were 50 g; the others fell between these extremes. A. How many genes are needed to explain the inheritance of weight in these frogs? Show your calculations. B. What is the allelic contribution for this system? Show formula and your calculations. C. How many phenotypic classes should appear in the F2? In what proportion will each appear? Show formula and calculations.

Explanation / Answer

small frogs.........aa large frogs.........AA aa x AA------- Aa (intermediate weight) Aa x Aa A a A AA (large frog) Aa (intermediate) a Aa (intermediate) aa ( small frog) Out of every four frogs, one is small, one is large and two are intermediate. Two alleles have been necessary, one is small 'a' and another large'A' to contribute to intermediate weight.

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.