Discuss the main condition required for external fertilization.

Explanation

**Step-by-Step Text Solution:**

1. **Understanding External Fertilization**: External fertilization refers to the process where fertilization occurs outside the female's body. This typically happens in aquatic environments where both male and female gametes (sperm and eggs) are released into the water.

2. **Process of External Fertilization**: In external fertilization, both the male and female organisms release their gametes into the water simultaneously. This process is often referred to as spawning.

3. **Main Condition for Success**: The primary condition required for successful external fertilization is the production of a large number of gametes. Both male and female gametes need to be released in significant quantities to increase the chances of fertilization occurring.

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