Membrane pathways for minerals along permeases

Options

A. need ATP
B. need carrier solute complex
C. need pinosomes
D. need diffusion gradient

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the membrane pathways for minerals and their relationship with permeases. It is important to clarify what permeases are and how they function in the transport of minerals across cell membranes.

2. **Defining Permeases**: Permeases are specialized membrane proteins that facilitate the transport of specific substances, including minerals, across the cell membrane. They act as carriers that bind to the solute (in this case, minerals) and help them move through the membrane.

3. **Role of ATP**: While some transport processes require ATP (energy), not all mineral transport through permeases is ATP-dependent. It is essential to distinguish between active and passive transport. Active transport requires energy, while passive transport does not.

4. **Carrier-Solute Complex**: The formation of a carrier-solute complex is crucial for the transport of minerals. The permease binds to the mineral, forming a complex that allows the mineral to be transported across the membrane.

5. **Diffusion Gradient**: The diffusion gradient is a key concept in the movement of minerals. It refers to the difference in concentration of minerals across the membrane. Minerals will naturally move from an area of higher concentration to an area of lower concentration, which is known as passive transport.

6. **Conclusion**: In summary, the transport of minerals along permeases primarily relies on the diffusion gradient. This means that minerals move down their concentration gradient, which does not require energy (ATP). Therefore, the correct answer to the question is that minerals need a diffusion gradient for transport along permeases.