Who is responsible for the sex of the chicks ?

Options

A. sperm
B. egg
C. temperature
D. hormones

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks who is responsible for determining the sex of chicks. This involves understanding the genetics of birds, particularly chickens.

2. **Identifying the Type of Gametes**: In birds, including chickens, the female is known to produce two types of gametes. This is referred to as female heterogamity.

3. **Understanding Female Heterogamity**: In female heterogamity, the female produces two different types of sex chromosomes in her eggs. In the case of birds, these are the Z and W chromosomes.

4. **Sex Determination in Birds**: In birds, the sex of the offspring is determined by the type of egg that is fertilized. The egg carries either a Z or a W chromosome.

5. **Specifics for Chickens**: In chickens, the sex determination system follows the ZW system. If the egg contains a W chromosome and is fertilized by a Z chromosome from the male, the resulting chick will be female (ZW). If the egg contains a Z chromosome and is fertilized by a Z chromosome from the male, the resulting chick will be male (ZZ).

6. **Conclusion**: Therefore, the female's egg is responsible for determining the sex of the chicks. The correct answer to the question is that the egg determines the sex of the chicks.

**Final Answer**: The egg is responsible for the sex of the chicks.

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