E.R. was discovered by

Options

A. Palade
B. Porter
C. Thomson
D. Both B and C

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the discovery of the endoplasmic reticulum (E.R.). We need to identify the scientist or scientists responsible for this discovery.

2. **Analyzing the Options**: The question likely provides multiple-choice options. We will evaluate each option to determine who discovered the E.R.

3. **Option 1 - Pellade**: Pellade is known as a founder of modern cell biology and is often referred to as the "father of cell biology." However, he did not discover the endoplasmic reticulum; he contributed to our understanding of ribosomes. Therefore, this option is incorrect.

4. **Option 2 - Porter**: Keith R. Porter is one of the scientists credited with the discovery of the endoplasmic reticulum. Along with him, two other scientists, Albert Claude and Ernest F. Flume, also contributed to this discovery. This makes option 2 the correct answer.

5. **Option 3 - Thomson**: Thomson is known for his work in physics, particularly for discovering the electron. He did not contribute to the discovery of the endoplasmic reticulum, making this option incorrect as well.

6. **Conclusion**: The correct answer to the question "E.R. was discovered by" is option 2, which includes Keith R. Porter, Albert Claude, and Ernest F. Flume.

**Final Answer**: The endoplasmic reticulum was discovered by Keith R. Porter, Albert Claude, and Ernest F. Flume.

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