Which type of gene regulates sex determination in spinach plant

Options

A. Homozygous genes
B. Single gene
C. Heterozygous genes
D. Multiple genes

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks which type of gene regulates sex determination in spinach plants. This involves understanding the genetic mechanisms behind sex determination in this species.

2. **Concept of Sex Determination**: In plants, sex determination is the process that decides whether an individual will develop into a male or female. This process often involves specific genes and chromosomes.

3. **Sex Chromosomes in Spinach**: Spinach has a specific set of chromosomes known as sex chromosomes or allosomes, which are responsible for determining the sex of the plant. In spinach, these chromosomes differ in morphology and number between males and females.

4. **Genetic Composition of Spinach**: Spinach is a diploid organism, meaning it has two sets of chromosomes. In the case of spinach, the diploid number of sex chromosomes is 2n = 12.

5. **Types of Genes Involved**: The sex determination in spinach is regulated by the presence of X and Y sex chromosomes. The combination of these chromosomes leads to the determination of male or female characteristics.

6. **Identifying the Type of Gene**: The presence of both X and Y chromosomes indicates that spinach has heterozygous genes. Heterozygous refers to having two different alleles for a particular gene, which in this case are the X and Y chromosomes.

7. **Final Answer**: Therefore, the type of gene that regulates sex determination in spinach plants is a **heterozygous gene**.