Question

which statements are properties of protein - based active transport?
☐ substances move from an area of lower concentration to an area of higher concentration.
☐ the cell spends energy to move substances through a protein across the plasma membrane.
☐ the cell spends energy to form vesicles to transport substances across the plasma membrane.
☐ substances pass through the plasma membrane without using any energy from the cell.
☐ nonpolar substances diffuse through the plasma membrane.

Explanation:

1. Recall the definition of protein - based active transport: Active transport is the movement of substances against their concentration gradient (from lower to higher concentration) and it requires energy (usually in the form of ATP) and a transport protein.

• For the statement "Substances move from an area of lower concentration to an area of higher concentration": This is a key property of active transport as it moves against the concentration gradient.
• For the statement "The cell spends energy to move substances through a protein across the plasma membrane": Active transport needs energy (e.g., ATP) and uses transport proteins to move substances across the membrane.
• For the statement "The cell spends energy to form vesicles to transport substances across the plasma membrane": This is a property of vesicular transport (like endocytosis or exocytosis), not protein - based active transport.
• For the statement "Substances pass through the plasma membrane without using any energy from the cell": This is passive transport (like diffusion or facilitated diffusion), not active transport.
• For the statement "Nonpolar substances diffuse through the plasma membrane": This is simple diffusion (a type of passive transport) for non - polar molecules, not active transport.

Answer:

• Substances move from an area of lower concentration to an area of higher concentration.
• The cell spends energy to move substances through a protein across the plasma membrane.