Transport Mechanisms in Cells

Scenario: In the lungs, oxygen molecules move from the air sacs (where there is a higher concentration of oxygen) into the bloodstream (where the oxygen concentration is lower). Similarly, carbon dioxide moves from the blood (high concentration) into the lungs (low concentration) to be exhaled.
Question:

• Is this passive or active transport?

• Active Transport

• Passive Transport

• Facilitated Transport

• Osmosis

Scenario: A nerve cell pumps sodium ions out of the cell, where sodium is already in higher concentration, and pumps potassium ions into the cell, where potassium is also more concentrated. This process uses ATP as an energy source.

Question:

• Is this passive or active transport?

• Passive Transport

• Active Transport

• Facilitated Diffusion

• Simple Diffusion

Scenario: After eating, glucose molecules in the bloodstream are transported into muscle cells to provide energy. The glucose concentration is higher in the blood and lower in the muscle cells. Transport proteins facilitate glucose movement into the cells without using energy.

Question:

• Is this passive or active transport?

• Active Transport

• Passive Transport

• Endocytosis

• Exocytosis

Scenario: Water molecules move from the soil (high water concentration) into the roots of a plant (low water concentration) through the root cell membranes. This process does not require energy.

Question:

• Is this passive or active transport?

• Active Transport

• Passive Transport

• Facilitated Diffusion

• Endocytosis

Scenario: During cellular respiration, protons (H⁺ ions) are pumped from the inside of the mitochondria to the intermembrane space, where the concentration of protons is already high. This movement requires energy from ATP.

Question
Is this passive or active transport?

• Passive Transport

• Facilitated Diffusion

• Active Transport

• Simple Diffusion