Monosomics are:

Options

A. No crossing over
B. 2n+1
C. 2n-2
D. 2n-1

Answer

**Step-by-Step Solution:**

1. **Understanding Monosomics**: Monosomics are a type of aneuploidy where an organism has a diploid chromosome number but is missing one chromosome from a pair.

2. **Defining the Chromosome Number**: In a typical diploid organism, the chromosome number is represented as 2n, where "n" is the number of pairs of chromosomes.

3. **Identifying the Missing Chromosome**: Since monosomics are characterized by the absence of one chromosome from a pair, the chromosome number would be reduced by one.

4. **Calculating the Chromosome Count**: Therefore, if we start with a diploid number of chromosomes (2n) and subtract one chromosome, the resulting chromosome count is 2n - 1.

5. **Conclusion**: Thus, the correct representation of monosomics in terms of chromosome number is 2n - 1.

**Final Answer**: Monosomics are represented as 2n - 1.

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