Entry of ions into the cell across the plasma membrane occurs to maintain electrical equilibrium was proposed by:

Options

A. Hylmo
B. Overstreet
C. Donnan
D. Home'

Answer

To solve the question "Entry of ions into the cell across the plasma membrane occurs to maintain electrical equilibrium was proposed by:", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Question**: The question is asking for the scientist who proposed the concept that ions enter cells to maintain electrical equilibrium across the plasma membrane.

2. **Identifying Key Terms**: The key terms in the question are "ions," "plasma membrane," and "electrical equilibrium." This indicates that the answer is related to a scientific principle regarding ion movement and membrane dynamics.

3. **Recalling Relevant Concepts**: The concept of electrical equilibrium in cells is often associated with the behavior of ions across a semi-permeable membrane. This is where the idea of equilibrium between two solutions separated by a membrane comes into play.

4. **Identifying the Scientist**: The scientist who is known for proposing the idea of equilibrium in relation to ion movement across membranes is Frederick G. Donnan.

5. **Understanding Donnan Equilibrium**: The term "Donnan equilibrium" refers to the state where the concentration of ions is balanced on both sides of a membrane, taking into account the permeability of the membrane to different ions. This equilibrium is crucial for maintaining the electrical potential across the plasma membrane.

6. **Final Answer**: Therefore, the answer to the question is that the entry of ions into the cell across the plasma membrane to maintain electrical equilibrium was proposed by Frederick G. Donnan.