In birds, femals are reprsented by chromsome

Options

A. XX
B. ZZ
C. ZO
D. ZW

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the representation of female chromosomes in birds. We need to identify the specific chromosomes that characterize female birds.

2. **Identifying Chromosome Types**: In birds, there are two types of sex chromosomes: Z and W.

3. **Female Chromosome Composition**: Female birds have one Z chromosome and one W chromosome. This is represented as ZW.

4. **Male Chromosome Composition**: In contrast, male birds have two Z chromosomes, represented as ZZ.

5. **Defining Female Heterogamy**: The presence of two different sex chromosomes (ZW) in females is an example of female heterogamy. This is different from male heterogamy, where males have two different chromosomes (XY in humans).

6. **Conclusion**: Therefore, in birds, females are represented by the chromosome combination ZW.

### Final Answer:
In birds, females are represented by the chromosome ZW.

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