If there are 999 bases in RNA that codes for a protein with 333 amino acids, and the base at position 901 is deleted such that the length of the RNA becomes 998 bases, how many codons will be altered

Options

A. 1
B. 11
C. 33
D. 333

Explanation

To solve the problem, we need to analyze the effect of deleting a base from the RNA sequence on the codons that are formed. Here’s a step-by-step breakdown of the solution:

### Step 1: Understand the relationship between bases and codons
- Each codon consists of 3 bases.
- Therefore, the number of codons in the original RNA sequence can be calculated by dividing the total number of bases by 3.

**Calculation:**
- Total bases = 999
- Number of codons = 999 bases / 3 bases per codon = 333 codons

### Step 2: Analyze the effect of the deletion
- When the base at position 901 is deleted, the total number of bases becomes 998.
- This deletion will affect the codons starting from the position of the deletion onward.

### Step 3: Determine how many codons are affected
- The deletion at position 901 means that the codon that includes this base (which is the 301st codon, since 900 bases correspond to 300 codons) will be altered.
- Additionally, the next 99 bases (from position 902 to 999) will also be affected because the reading frame will shift due to the deletion.

**Calculation:**
- The codon at position 901 (301st codon) will be altered.
- The next 99 bases (which correspond to 33 codons, since 99 bases / 3 bases per codon = 33 codons) will also be altered.

### Step 4: Total number of altered codons
- The total number of altered codons will be the codon at position 901 plus the 33 subsequent codons affected by the deletion.

**Total altered codons:**
- 1 (for the codon at position 901) + 33 (for the next codons) = 34 codons.

### Final Answer:
The total number of codons that will be altered due to the deletion of the base at position 901 is **34 codons**.

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