Which of the following statements is true? -A codon can specify more than one amino acid
-some codons do not perform a function
-some codons specify the same amino acid
-each coat on specifies a unique amino acid

1. in what ways have non-native species been beneficial? 2. what are some of the hypotheses for the collapse of honeybee colonies? 3. distinguish between regional and functional extinction. 4. why is it difficult to measure background extinction rates? 5. what three factors are most important in causing extinction rates to climb?