The two types of ribosomes are

Options

A. `{:("Nucleus","cytoplasm"),("Free","fixed"):}`
B. `{:("Endoplasmic reticulum","Nucleus"),("fixed","Free"):}`
C. `{:("Endoplasmic reticulum","Nucleus"),("Free","fixed"):}`
D. `{:("cytoplasm","Nucleus"),("fixed","Free"):}`

Answer

### Step-by-Step Solution:

1. **Understanding Ribosomes**: Ribosomes are cellular structures responsible for protein synthesis. They can be found in different locations within the cell.

2. **Identifying the Two Types**: There are two main types of ribosomes:
- **Free Ribosomes**: These are located in the cytoplasm and are not attached to any organelle. They synthesize proteins that typically function within the cytosol.
- **Bound Ribosomes**: These are attached to the endoplasmic reticulum (ER), specifically the rough endoplasmic reticulum (RER). They synthesize proteins that are either secreted from the cell, incorporated into the cell’s plasma membrane, or sent to an organelle.

3. **Function of Ribosomes**: Both types of ribosomes perform the same fundamental function of translating mRNA into proteins, but their locations determine the destination and function of the proteins they produce.

4. **Conclusion**: The two types of ribosomes are:
- **Free Ribosomes**: Present in the cytoplasm.
- **Bound Ribosomes**: Attached to the rough endoplasmic reticulum.

### Final Answer:
The two types of ribosomes are:
1. Free Ribosomes (in the cytoplasm)
2. Bound Ribosomes (attached to the rough endoplasmic reticulum)

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