Answered

Explore Westonci.ca, the premier Q&A site that helps you find precise answers to your questions, no matter the topic. Experience the ease of finding quick and accurate answers to your questions from professionals on our platform. Our platform offers a seamless experience for finding reliable answers from a network of knowledgeable professionals.

Unattached earlobes are dominant to attached earlobes. Cleft chin is dominant to no cleft. Parents that are heterozygous for both traits are crossed.

Determine the ratio of offspring with the described trait to the total number of offspring:

- Unattached earlobes and cleft chin
- Unattached earlobes and no cleft
- Attached earlobes and cleft chin
- Attached earlobes and no cleft

[tex]\[
\begin{tabular}{l|c|c|c|c|}
\multicolumn{1}{c}{} & \multicolumn{1}{c}{EA} & \multicolumn{1}{c}{Ea} & \multicolumn{1}{c}{eA} & \multicolumn{1}{c}{ea} \\
\hline
EA & EEAA & EEAa & EeAA & EeAa \\
\hline
Ea & EEAa & EEaa & EeAa & Eeaa \\
\hline
eA & EeAA & EeAa & eeAA & eeAa \\
\hline
ea & EeAa & Eeaa & eeAa & eeaa \\
\hline
\end{tabular}
\][/tex]

Sagot :

GinnyAnswer
Certainly! Let's determine the ratio of offspring with each described trait to the total number of offspring when parents heterozygous for both traits are crossed.

### Genetic Background:
1. Unattached earlobes (E) are dominant to attached earlobes (e).
2. Cleft chin (A) is dominant to no cleft chin (a).
3. Both parents are heterozygous for both traits (genotype EeAa).

### Determining Genotypes:
When we cross two heterozygous parents (EeAa), we need to set up a Punnett square to consider all possible combinations of alleles for the offspring.

### Punnett Square:
Below is the 4x4 Punnett square for the cross of EeAa x EeAa:

| | EA | Ea | eA | ea |
|----------|----------|---------|---------|---------|
| EA | EEAA | EEAa | EeAA | EeAa |
| Ea | EEAa | EEaa | EeAa | Eeaa |
| eA | EeAA | EeAa | eeAA | eeAa |
| ea | EeAa | Eeaa | eeAa | eeaa |

### Phenotypes and Corresponding Genotypes:
1. Unattached earlobes and cleft chin (E_A_):
- Genotypes: EEAA, EEAa, EeAA, EeAa
2. Unattached earlobes and no cleft chin (E_aa):
- Genotypes: EEaa, Eeaa
3. Attached earlobes and cleft chin (eeA_):
- Genotypes: eeAA, eeAa
4. Attached earlobes and no cleft chin (eeaa):
- Genotype: eeaa

### Counting the Genotypes:
From the Punnett square, we can count the number of occurrences of each genotype that corresponds to the phenotypes mentioned:

1. Unattached earlobes and cleft chin (EEAA, EEAa, EeAA, EeAa)
- Count: 9

2. Unattached earlobes and no cleft chin (EEaa, Eeaa)
- Count: 3

3. Attached earlobes and cleft chin (eeAA, eeAa)
- Count: 3

4. Attached earlobes and no cleft chin (eeaa)
- Count: 1

### Ratios:
Thus, the ratio of offspring with each described phenotype to the total number of offspring is:
1. Unattached earlobes and cleft chin: 9
2. Unattached earlobes and no cleft chin: 3
3. Attached earlobes and cleft chin: 3
4. Attached earlobes and no cleft chin: 1

This can also be written in the form 9:3:3:1.
We hope this information was helpful. Feel free to return anytime for more answers to your questions and concerns. Your visit means a lot to us. Don't hesitate to return for more reliable answers to any questions you may have. We're glad you visited Westonci.ca. Return anytime for updated answers from our knowledgeable team.