Answer:
Early geneticists wondered how only four nucleotides can specify the sequence of 20 amino acids in proteins. They hypothesized that there must be a code that linked the nucleotide sequence in a gene to the amino acid sequence in a protein. Each nucleotide code is called a codon. Today we know that there is a genetic code in which __________nucleotide(s) code(s) for each amino acid.
3
4
1
2
Explanation:
3 is the answer. 43 or 64 is the number of possible 3-letter codes that can be formed.
more than one codon can codes for the same amino acid
(Variation.)Heritable differences that exist in every population are the basis for natural selection.
(Overproduction). Competition between offsprings for resources.
(Adaptation.) a trait that helps an organism survive and reproduce.
Descent with Modification.
Photosynthieis sry if spelled wrong
Grade aa eggs are nearly perfect