Crossing over produces:

Options

A. Recombination of linked gens
B. Synapsis of linked genes
C. Expression of recessive genes
D. Linkage of dominant genes

Answer

**Step-by-Step Solution:**

1. **Understanding Crossing Over**:
- Crossing over is a biological process that occurs during meiosis, where homologous chromosomes exchange segments of their genetic material. This process is crucial for genetic diversity.

2. **Identifying the Function of Crossing Over**:
- The primary function of crossing over is to create new combinations of alleles (gene variants) on chromosomes. This leads to genetic variation in the offspring.

3. **Evaluating the Options**:
- The options given are:
a) Recombination of linked genes
b) Synapses of linked genes
c) Expression of recessive genes
d) Linkage of dominant genes

4. **Analyzing Each Option**:
- **Recombination of linked genes**: This is the correct answer as crossing over leads to the exchange of genetic material between homologous chromosomes, resulting in new allele combinations.
- **Synapses of linked genes**: Synapsis refers to the pairing of homologous chromosomes, not the exchange of genetic material. Thus, this option is incorrect.
- **Expression of recessive genes**: Crossing over does not directly cause the expression of recessive genes; it merely alters allele combinations.
- **Linkage of dominant genes**: This option is misleading as crossing over can disrupt linkage rather than promote it.

5. **Conclusion**:
- Based on the analysis, the correct answer is **recombination of linked genes**. This process is essential for increasing genetic variation in sexually reproducing organisms.

**Final Answer**: Crossing over produces **recombination of linked genes**.

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