In a certain taxon of insects some have 17 chromosomes and the others have 18 chromosomes. The 17 and 18 chromosome-bearing organisms are

Options

A. males and frmales, respectively
B. femelses and males, respectively
C. all males
D. all frmales

Explanation

To solve the question regarding the insects with 17 and 18 chromosomes, we can follow these steps:

### Step 1: Understand Chromosome Composition
In the given taxon of insects, we have two different chromosome counts: 17 and 18. We need to analyze what these numbers represent in terms of sex determination.

### Step 2: Identify the Sex Determination System
Insects often utilize the XO/XX system for sex determination. In this system:
- Males are represented by the XO configuration (one sex chromosome).
- Females are represented by the XX configuration (two sex chromosomes).

### Step 3: Calculate the Total Chromosome Count
In addition to the sex chromosomes, insects have autosomes (non-sex chromosomes).
- For males (XO), they have 16 autosomes + 1 sex chromosome = 17 chromosomes total.
- For females (XX), they have 16 autosomes + 2 sex chromosomes = 18 chromosomes total.

### Step 4: Conclusion
From the above analysis, we can conclude:
- The organisms with 17 chromosomes are males (XO).
- The organisms with 18 chromosomes are females (XX).

### Final Answer
The 17 chromosome-bearing organisms are males, and the 18 chromosome-bearing organisms are females.

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