What is the difference between a pure tall plant and a hybrid tall plant?

The pure tall plant has equal alleles (AA or aa) while the hybrid tall plant has one dominant and recessive allele (Aa).

Explanation:

When we say that an organism is pure, we mean that it is homozygous. In this case we are saying that, for a given trait, its alleles are equal. This means that the allele is occurring in double dose in that organism and, consequently, the gametes generated by it will be equal. A pure tall plant has alleles equal to "AA" or "aa".

When we refer to hybrid organisms, we are referring to heterozygous organisms. In this case we are saying that, for a certain characteristic, the alleles are different. For this reason, in gametogenesis, it is possible to observe the presence of two distinct gametes. A hybrid tall plant has different "Aa" alleles.

Amino acid sequences

Explanation:

The proteins perform the vast majority of functions in the cells. If a gene between a human and a mouse is evolutionarily related, it means that the function they do in the cell is quite similar in both species. This is the reason why the amino acid sequence would be the most similar.

In addition, there might be certain mutations in the DNA and therefore in the RNA between this 2 sequences that encode to the same amino acid sequence. More specifically speaking, there are more than one codon that encode to the same aminoacid. Thus, 2 different DNA/RNA sequence can give the same aminoacid sequence.