the long and short arms of chromosome are designated respectively as :

Options

A. p and q
B. q and p
C. `alpha and beta`
D. m and p

Answer

To answer the question regarding the designations of the long and short arms of a chromosome, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Chromosome Structure**:
- A chromosome consists of two arms separated by a centromere.

2. **Identifying the Arms**:
- The two arms of the chromosome are referred to as the short arm and the long arm.

3. **Designation of the Short Arm**:
- The short arm of the chromosome is designated by the letter "P".
- The letter "P" is derived from the French word "petite," which means small.

4. **Designation of the Long Arm**:
- The long arm of the chromosome is designated by the letter "Q".
- The letter "Q" is thought to come from the word "queue," which means tail.

5. **Conclusion**:
- Therefore, the long and short arms of a chromosome are designated respectively as P (short arm) and Q (long arm).

### Final Answer:
The long and short arms of a chromosome are designated respectively as P and Q.

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