What does the notation Tt represent for the trait of being tall?

In the notation Tt, each letter represents an allele for a specific gene or trait. In this context, considering the trait of being tall:

• T (uppercase) represents the dominant allele for tallness.
• t (lowercase) represents the recessive allele for shortness.

Therefore, in the notation Tt:

• The uppercase "T" represents one allele for tallness.
• The lowercase "t" represents one allele for shortness.

The presence of both alleles, Tt, indicates that the organism is heterozygous for the trait of being tall, meaning it carries both the dominant (T) and recessive (t) alleles. In cases where "T" represents the dominant allele for tallness and "t" represents the recessive allele for shortness, the dominant allele (T) often determines the observed trait, resulting in the organism being tall due to the presence of at least one dominant allele.