Endoplasmic reticulum arises from

Options

A. Inner karyotheca
B. Outer karyotheca
C. Plasmamembrane
D. Endomembrane system

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks where the endoplasmic reticulum (ER) arises from. To answer this, we need to explore the structure of the cell and the components involved in the formation of the ER.

2. **Identifying the Options:**
The options provided are:
- Inner karyotheka
- Outer karyotheka
- Plasma membrane
- Endomembrane system

3. **Analyzing Each Option:**
- **Inner Karyotheka:** This refers to the inner part of the nuclear envelope, which contains the nucleus. The ER does not arise from this part.
- **Outer Karyotheka:** This is the outer part of the nuclear envelope. The endoplasmic reticulum is known to extend from this outer membrane.
- **Plasma Membrane:** This is the outer boundary of the cell, made up of a lipid bilayer. The ER does not originate from the plasma membrane.
- **Endomembrane System:** This system includes various organelles such as the ER, Golgi apparatus, lysosomes, and vacuoles. While the ER is part of this system, it does not specifically arise from it.

4. **Conclusion:**
The endoplasmic reticulum arises from the **outer karyotheka** (outer nuclear membrane). This is the correct answer as the ER extends from the outer part of the nuclear envelope.

5. **Final Answer:**
The endoplasmic reticulum arises from the outer karyotheka.

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