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In a certain variety of lentils, one gene controls color: red is completely dominant to orange, while a second independent gene controls pattern: large spots are co-dominant with small dots. A dihybrid cross involving these two genes should result in:

User Yagel
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1 Answer

3 votes

Answer:

a phenotypic ratio 9:3:3:1

Step-by-step explanation:

  • one gene controls color: red (R) is completely dominant to orange (r)
  • a second independent gene controls pattern: large spots (L) are co-dominant with small dots (l)
  • A dihybrid cross involving these two genes

Cross:

Parental) RrLl x RrLl

Gametes) RL Rl rL rl

RL Rl rL rl

Punnet Square) RL Rl rL rl

RL RRLL RRLl RrLL RrLl

Rl RRLl RRll RrLL Rrll

rL RrLL RrLl rrLL rrLl

rl RrLl Rrll rrLl rrll

F1) 9/16 R-L-, red and large spotted individuals

3/16 R-ll, red and small dotted individuals

3/16 rrL-, orange and large spotted individuals

1/16 rrll, orange and small dotted individuals

Note: The symbol "-" refers to either the dominant allele or the recessive one

User Mark Kramer
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