A condition where an individual heterozygous for two pairs of linked genes ( AaBb ) possesses the two dominant genes on one homologous chromosomes pair and two recessive on the other it is said to be

Options

A. Cis - arrangement
B. Trans - arrangement
C. Partly cls party trans
D. More than one option is correct

Answer

To solve the question regarding the arrangement of alleles in an individual heterozygous for two pairs of linked genes (AaBb), we need to understand the concepts of cis and trans arrangements.

### Step-by-Step Solution:

1. **Understanding Linked Genes**:
- Linked genes are genes that are located close to each other on the same chromosome and tend to be inherited together. In this case, we have two pairs of linked genes: A and B.

**Hint**: Remember that linked genes are inherited together due to their proximity on the chromosome.

2. **Identifying the Alleles**:
- The individual is heterozygous for the two genes, meaning it has one dominant and one recessive allele for each gene. Thus, the genotype is AaBb, where 'A' and 'B' are dominant alleles, and 'a' and 'b' are recessive alleles.

**Hint**: Heterozygous means having two different alleles for a particular gene.

3. **Understanding Chromosome Arrangement**:
- The question states that the two dominant alleles (A and B) are on one homologous chromosome, while the two recessive alleles (a and b) are on the other homologous chromosome. This specific arrangement is crucial for determining the type of linkage.

**Hint**: Visualize the homologous chromosomes and where the alleles are located on them.

4. **Defining Cis and Trans Arrangements**:
- In a **cis arrangement**, both dominant alleles are on one chromosome and both recessive alleles are on the other chromosome.
- In a **trans arrangement**, one dominant allele and one recessive allele are on each chromosome.

**Hint**: Cis means "together" (dominants together), while trans means "across" (dominants and recessives across the chromosomes).

5. **Conclusion**:
- Since the dominant alleles (A and B) are on one chromosome and the recessive alleles (a and b) are on the other, this arrangement is classified as a **cis arrangement**.

**Final Answer**: The correct answer is **A. cis arrangement**.