Question

how you would classify the transport carried out by na-k pumps which move na out of the cell? why do you choose this classification?
○ as facilitated diffusion as they use carrier proteins but no energy is required.
○ as simple diffusion as they transport na and k down a concentration gradient
○ as active transport as they transport against a concentration gradient and energy is utilized.
○ as osmosis as they use energy and transport against a concentration gradient

question 22
which of the following substances use transport proteins to cross the cell membrane?
○ o2
○ co2
○ h2o
○ glucose

Explanation:

Question 1 (Classification of Na-K pump transport)

1. Analyze each option:

• Facilitated diffusion: Requires no energy, moves down concentration gradient. Na - K pumps use energy, so this is wrong.
• Simple diffusion: No transport proteins, moves down gradient. Na - K pumps use proteins and move against gradient, so wrong.
• Active transport: Moves against concentration gradient and uses energy (ATP for Na - K pumps). This matches.
• Osmosis: Movement of water, not ions like Na/K, so wrong.

• \(O_2\), \(CO_2\), and \(H_2O\) move across cell membrane via simple diffusion (no transport proteins, small/non - polar or via aquaporins for water but the options here likely consider simple diffusion for water too). Glucose is a large polar molecule and uses transport proteins (e.g., GLUT transporters) to cross the cell membrane.

Answer:

As active transport as they transport against a concentration gradient and energy is utilized.

Question 2 (Substances using transport proteins)