Question

look again at the partial gene sequences and their translations.
sequence 1:
caacccagtga
part of a gene
sequence
translated amino
acid sequence
valine
serine
proline

sequence 2:
caactcagaga
part of a gene
sequence
translated amino
acid sequence
glutamine
leucine
serine
arginine

how many of the amino acids in sequence 2 are different from the amino acids in sequence 1?

why are the translations of sequence 1 and sequence 2 different? select all that apply.
sequence 1 and sequence 2 have different numbers of codons.
sequence 1 and sequence 2 have different nucleotide sequences.
sequence 1 and sequence 2 have different numbers of nucleotides.

Explanation:

First Sub - Question (How many amino acids differ?)

Step 1: List amino acids of each sequence

Sequence 1 (CAACCCAGTTA) translated amino acids: Glutamine, Proline, Serine, Valine.
Sequence 2 (CAACTCAGTGA) translated amino acids: Glutamine, Leucine, Serine, Arginine.

Step 2: Compare each position

• Position 1: Both Glutamine (same).
• Position 2: Proline vs Leucine (different).
• Position 3: Serine (same).
• Position 4: Valine vs Arginine (different).
• Count the different ones: 2.

• Analyze each option:
• "Sequence 1 and sequence 2 have different numbers of codons": Both sequences have 4 codons (since each amino acid is coded by a codon, 4 amino acids each, so 4 codons), so this is wrong.
• "Sequence 1 and sequence 2 have different nucleotide sequences": The gene sequences (nucleotide sequences) are different (CAACCCAGTTA vs CAACTCAGTGA), which changes the codons and thus the amino acids translated, so this is correct.
• "Sequence 1 and sequence 2 have different numbers of nucleotides": Both sequences have 12 nucleotides (4 codons × 3 nucleotides per codon), so this is wrong.

Answer:

2

Second Sub - Question (Why are translations different?)