Question 3How many DNA strings transcribe and translate into the amino acid string LEADER?

To determine how many DNA strings transcribe and translate into the amino acid string LEADER, we need to follow a step-by-step process:

Step 1: Convert the amino acid string LEADER into its corresponding RNA sequence. The RNA sequence is obtained by replacing each amino acid with its corresponding codon. For example, the codon for the amino acid L (leucine) is UUA, the codon for E (glutamic acid) is GAA, and so on. Therefore, the RNA sequence for the amino acid string LEADER would be UUA GAA GAG GAA CGU.

Step 2: Reverse transcribe the RNA sequence to obtain the complementary DNA sequence. In this step, we replace each RNA base with its complementary DNA base. For example, U (uracil) is replaced with A (adenine), A (adenine) is replaced with T (thymine), G (guanine) is replaced with C (cytosine), and C (cytosine) is replaced with G (guanine). Therefore, the complementary DNA sequence for the RNA sequence UUA GAA GAG GAA CGU would be AAT CTT CTC CTT GCT.

Step 3: Generate all possible DNA sequences that can be formed from the complementary DNA sequence obtained in step 2. This can be done by considering all possible combinations of the four DNA bases (A, T, G, C) at each position in the sequence. For example, at the first position, we can have A, T, G, or C. Similarly, at the second position, we can have A, T, G, or C, and so on. By considering all possible combinations, we can generate a list of DNA sequences.

Step 4: Translate each DNA sequence obtained in step 3 into its corresponding amino acid sequence. This can be done by considering each codon (three DNA bases) and determining the corresponding amino acid. For example, the codon ATG corresponds to the amino acid M (methionine), the codon GAA corresponds to the amino acid E (glutamic acid), and so on. By translating each DNA sequence, we can obtain a list of amino acid sequences.

Step 5: Count the number of amino acid sequences that match the desired amino acid string LEADER. Compare each amino acid sequence obtained in step 4 with the desired amino acid string LEADER. If a match is found, increment the count.

Step 6: The final count obtained in step 5 represents the number of DNA strings that transcribe and translate into the amino acid string LEADER.

Please note that the actual implementation of these steps may require the use of bioinformatics tools or programming languages specifically designed for DNA sequence analysis.