Which is not a correct match?

Options

A. Sex determination- chromosomal phenomenon
B. Red green colour blindness- sex linked charcter
C. Abnormal chromsosome number -polyploidy
D. Y- chromosome autosomal

Answer

To determine which option is not a correct match, we need to analyze the given pairs related to sex determination and chromosomal phenomena. Let's break down the options step by step:

### Step 1: Identify the pairs
The options presented include:
1. Sex determination - Chromosomal phenomenon
2. Red-green color blindness - Sex-linked character
3. Abnormal chromosome number - Polyploidy
4. Y chromosome - Autosomal

### Step 2: Analyze each pair
1. **Sex determination - Chromosomal phenomenon**: This is a correct match. The chromosomal theory of sex determination states that the sex of an individual is determined by the type of sex chromosomes (XX for females and XY for males).

2. **Red-green color blindness - Sex-linked character**: This is also a correct match. Red-green color blindness is indeed a sex-linked trait, primarily located on the X chromosome, affecting males more frequently than females.

3. **Abnormal chromosome number - Polyploidy**: This is a correct match as well. Polyploidy refers to a condition in which an organism has more than two complete sets of chromosomes, which is a type of abnormal chromosome number.

4. **Y chromosome - Autosomal**: This is the incorrect match. The Y chromosome is a sex chromosome (also known as an allosome), not an autosome. Autosomes are the chromosomes that are not involved in sex determination.

### Conclusion
The option that is not a correct match is **Y chromosome - Autosomal**.

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