Answer: Natural selection can act on traits determined by alternative alleles of a single gene ... hope this helps, this is one of many answers for this question!
I think burgess shells would be the answer
Sickel cell anemia is an inherited disease that is due to a base substitution mutation in a gene.
I believe that the answer to your question would be A. Heart Begins.
Answer:
One amino acid
Explanation:
This question is describing the occurrence of the process of mutation, which is the alteration in the genetic sequence of a gene. In this question, a DNA sequence was given as follows: TAC-ATC-CAT-CAG-TTA-CGC. However, a SUBSTITUTION MUTATION took place in such a way that the thymine base was replaced by a guanine base to have mutated sequence: GAC-ATC-CAT-CAG-TTA-CGC.
Since the mutation is a kind of substitution mutation, only the codon affected by that mutation will change. This DNA sequence will be transcribed into a mRNA sequence. The mRNA will be read codon by codon (a group of hree nucleotides) to produce amino acid. Since one codon will be involved, one amino acid will be affected.