The function of the gap junction is to

Options

A. performing cementing to keep neighbouring cells together .
B. facilitate communication between adjoining cells by connecting the cytoplasm
for rapid transfer of ions, small molecules and some large molecules
C. separate two cells from each other
D. stop substance from leaking across a tissue

Answer

### Step-by-Step Solution:

1. **Understanding Gap Junctions**:
- Gap junctions are specialized intercellular connections found in animal cells. They play a crucial role in cellular communication.

2. **Function of Gap Junctions**:
- The primary function of gap junctions is to facilitate communication between adjacent cells. They achieve this by connecting the cytoplasm of two cells directly.

3. **Transfer of Molecules**:
- Gap junctions allow for the rapid transfer of ions, small molecules, and even some larger molecules between cells. This is essential for various physiological processes, including electrical signaling in tissues like the heart.

4. **Evaluating Options**:
- **Option 1**: Performing cementing to keep neighboring cells together - This describes desmosomes, not gap junctions.
- **Option 2**: Facilitate communication between adjoining cells by connecting the cytoplasm for rapid transfer of ions, small molecules, and some large molecules - This accurately describes the function of gap junctions.
- **Option 3**: Separate two cells from each other - This is incorrect as gap junctions connect cells rather than separate them.
- **Option 4**: Stop substances from leaking across a tissue - This describes tight junctions, not gap junctions.

5. **Conclusion**:
- Based on the evaluation of the options, the correct answer is **Option 2**: "Facilitate communication between adjoining cells by connecting the cytoplasm for rapid transfer of ions, small molecules, and some large molecules."