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For sneaky snakes, being rude (R) is dominant to being respectful (r). Complete the cross below, and determine the phenotype (dominant : recessive) ratio. R r r #1 #2 r #3 #4 2 (#5) : 2 (#6) Column A 1. #1: #1 2. #2: #2 3. #3: #3 4. #4: #4 5. #5: #5 6. #6: #6 Column B a.rr b.respectful c.Rr d.RR e.sneaky f.rude g.sweet

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To complete the cross for sneaky snakes, we can set up a Punnett square based on the genotypes of the parents. Given that "R" (rude) is dominant over "r" (respectful), we can assume that you're looking at crosses between different combinations of these alleles.

Let's assume the following two crosses:

  1. RR x rr (homozygous dominant with homozygous recessive)
  2. Rr x Rr (heterozygous)

1. Cross: RR x rr

| | R | R | |-------|-------|-------| | r | Rr | Rr | | r | Rr | Rr |

Phenotypes:

  • All snakes would be Rr (rude).

2. Cross: Rr x Rr

| | R | r | |-------|-------|-------| | R | RR | Rr | | r | Rr | rr |

Phenotypes:

  • RR: 1 (rude)
  • Rr: 2 (rude)
  • rr: 1 (respectful)

Ratio of phenotypes:

  • Rude (dominant): 3 (RR + Rr)
  • Respectful (recessive): 1 (rr)

So the ratio of dominant to recessive phenotypes is 3:1.

Assignment of values:

Using the columns provided, here are the matching values based on the information you've given:

| # | Phenotype | |----|---------------| | #1 | R | c. Rr | | #2 | R | d. RR | | #3 | r | a. rr | | #4 | R | e. sneaky | | #5 | 3 | (Rude = 3) | | #6 | 1 | (Respectful = 1)|

Thus, the complete answer is:

  • Ratio of dominant to recessive phenotypes: 3 (rude) : 1 (respectful).