At the metaphase plate during metaphase I of meiosis, there are

Options

A. single chromosomes
B. always twenty-three chromosomes
C. bivalents
D. unpaired duplicated chromosomes

Answer

To answer the question about what is present at the metaphase plate during metaphase I of meiosis, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Meiosis**: Meiosis is a type of cell division that reduces the chromosome number by half, resulting in four haploid cells. It consists of two sequential divisions: meiosis I and meiosis II.

2. **Phases of Meiosis I**: Meiosis I includes several phases: prophase I, metaphase I, anaphase I, and telophase I. The question specifically refers to metaphase I.

3. **Prophase I**: During prophase I, homologous chromosomes pair up and exchange genetic material through a process called crossing over. This pairing forms structures known as bivalents (or tetrads), which consist of two homologous chromosomes, each made up of two sister chromatids.

4. **Metaphase I**: In metaphase I, the bivalents align along the metaphase plate. This is the key feature of metaphase I, as it is during this stage that the bivalents are positioned for separation.

5. **Identifying the Correct Answer**: The question asks what is present at the metaphase plate during metaphase I. Since bivalents are the structures that align at the metaphase plate, the correct answer is **C. bivalents**.

### Final Answer:
The correct answer is **C. bivalents**.

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