Ion carriers are located in

Options

A. Nucleus
B. Cell wall
C. Cellular space
D. Plasma membranes

Answer

To solve the question "Ion carriers are located in," we will evaluate each option provided and determine where ion carriers are actually found.

### Step-by-Step Solution:

**Step 1: Analyze the first option - Nucleus**
- The nucleus is a double membrane-bound organelle found in eukaryotic cells.
- It contains genetic material in the form of chromosomes and is responsible for controlling cellular activities, including protein synthesis.
- Ion carriers are not involved in the functions of the nucleus.
- **Conclusion**: Ion carriers are NOT located in the nucleus.

**Step 2: Analyze the second option - Cell Wall**
- The cell wall is present in both prokaryotic and eukaryotic cells, primarily in plant cells (made of cellulose).
- While the cell wall does facilitate the transport of some molecules, it is generally permeable and does not regulate the transport of ions.
- **Conclusion**: Ion carriers are NOT located in the cell wall.

**Step 3: Analyze the third option - Cellular Space**
- Cellular space refers to the areas between cells, which contain various junctions that help in the exchange of materials.
- However, these spaces do not contain ion carriers; they are more about facilitating communication and transport between cells.
- **Conclusion**: Ion carriers are NOT located in the cellular space.

**Step 4: Analyze the fourth option - Plasma Membrane**
- The plasma membrane surrounds the cell and is selectively permeable, meaning it allows certain molecules to pass while restricting others.
- Ion carriers, such as channel proteins, are embedded in the plasma membrane to facilitate the transport of ions and large polar molecules that cannot pass through the membrane freely.
- **Conclusion**: Ion carriers ARE located in the plasma membrane.

### Final Answer:
Ion carriers are located in the **plasma membrane**.

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