Z-chromosome in birds is the name for

Options

A. Y-chromsome in males
B. X-chromosomes, and is paired in males
C. X-chromosome and is unpaired in males
D. Y-chromosome in females

Answer

### Step-by-Step Solution:

1. **Understanding Chromosome Types in Birds**: In birds, the sex determination system is different from that in humans. Birds have a ZW sex-determination system, where males are ZZ and females are ZW.

2. **Identifying the Z Chromosome**: The Z chromosome in birds is analogous to the X chromosome in mammals. This means that the Z chromosome carries genes that are involved in sex determination and other traits.

3. **Comparing with Human Chromosomes**: In humans, males have XY chromosomes (heterozygous) and females have XX chromosomes (homozygous). In contrast, in birds, males are homozygous (ZZ) and females are heterozygous (ZW).

4. **Conclusion**: Therefore, the Z chromosome in birds can be referred to as the equivalent of the X chromosome in mammals, as it is present in a homozygous state in males and plays a crucial role in sex determination.

### Final Answer:
The Z chromosome in birds is analogous to the X chromosome in mammals.

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