Which of the following statements is incorrect about the Golgi apparatus?

Options

A. The sacs on the forming face (cis-face) are associated with ER.
B. Golgi apparatus was studied by Camillo Golgi in the nerve cells of owl by metallic impregnation technique
C. Golgi apparatus in plants is called as dictyosome and secretes mucilage in the root cap cells.
D. Golgi apparatus has no role in the modification of proinsulin

Answer

To determine which statement about the Golgi apparatus is incorrect, we can analyze each of the provided statements one by one.

### Step-by-Step Solution:

1. **Evaluate the First Statement**:
- The first statement claims that the "cis face of the Golgi apparatus is associated with the endoplasmic reticulum (ER)."
- This statement is **correct**. The cis face of the Golgi apparatus is indeed the receiving side, where it receives vesicles from the rough ER.

**Hint**: Remember the orientation of the Golgi apparatus and its relationship with the ER.

2. **Evaluate the Second Statement**:
- The second statement states that "Golgi apparatus was studied by Camillo Golgi in the nerve cells of owls using the metallic impregnation technique."
- This statement is also **correct**. Camillo Golgi discovered the Golgi apparatus in 1898, and he used a staining technique to observe it in nerve cells.

**Hint**: Recall the historical context of the discovery of cellular structures.

3. **Evaluate the Third Statement**:
- The third statement mentions that "dictyosomes secrete mucilage in the root cap cells."
- This statement is **correct**. Dictyosomes (another name for Golgi apparatus) do secrete mucilage in root cap cells, which aids in protecting the root.

**Hint**: Consider the functions of the Golgi apparatus in plant cells.

4. **Evaluate the Fourth Statement**:
- The fourth statement claims that "Golgi apparatus has no role in the modification of pro-insulin."
- This statement is **incorrect**. The Golgi apparatus is crucial for the modification of pro-insulin. It processes pro-insulin into insulin and packages it into secretory vesicles.

**Hint**: Think about the role of the Golgi apparatus in protein processing and secretion.

### Conclusion:
The incorrect statement about the Golgi apparatus is the fourth one: "Golgi apparatus has no role in modification of pro-insulin."