The genotype for the height of an organism is Tt. What conclusion may be drawn from this?

Options

A. The allele for height has at least two different genes.
B. There are at least two different alleles for the gene for height.
C. There are two different genes for height, each having a single allele.
D. There is one allele for height with two different forms.

Explanation

To analyze the genotype Tt for the height of an organism, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Genotype**: The genotype refers to the genetic makeup of an organism, specifically the alleles it possesses for a particular trait. In this case, the genotype is Tt.

2. **Identifying Alleles**: The genotype Tt consists of two alleles: a dominant allele (T) and a recessive allele (t). The capital letter (T) represents the dominant trait, while the lowercase letter (t) represents the recessive trait.

3. **Dominance and Phenotype**: Since T is dominant, the phenotype (observable characteristic) of the organism will express the dominant trait associated with T. In this context, if T represents tall height, the organism will be tall.

4. **Heterozygous Condition**: The genotype Tt indicates a heterozygous condition, meaning the organism has two different alleles for the height trait. This is in contrast to a homozygous condition, where both alleles would be the same (TT or tt).

5. **Conclusion**: From the genotype Tt, we can conclude that the organism will exhibit the dominant phenotype (tall) due to the presence of the dominant allele T. Additionally, it indicates that there are at least two different alleles for the gene controlling height.

### Final Conclusion:
The conclusion drawn from the genotype Tt is that the organism will be tall due to the presence of the dominant allele T, and it also indicates that there are at least two different alleles for the gene for height.

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