Which take place in all eukaryotic organisms as a method of cellular defense

Answer

**Step-by-Step Solution:**

1. **Understanding Eukaryotic Organisms**: Eukaryotic organisms are defined as those that have cells with membrane-bound organelles, including a nucleus. Examples include plants, animals, fungi, and protists.

2. **Identifying Cellular Defense Mechanisms**: Cellular defense mechanisms are processes that cells use to protect themselves from harmful agents, such as viruses or transposable elements.

3. **Recognizing RNA Interference (RNAi)**: One of the key cellular defense mechanisms present in all eukaryotic organisms is RNA interference (RNAi). This is a process where RNA molecules inhibit gene expression or translation.

4. **Mechanism of RNAi**: In RNA interference, specific mRNA molecules are targeted and silenced. This means that the mRNA is neutralized, preventing it from being translated into proteins. This is achieved by small RNA molecules that bind to the mRNA, leading to its degradation or preventing its translation.

5. **Conclusion**: Therefore, RNA interference (RNAi) is the method that takes place in all eukaryotic organisms as a method of cellular defense.

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