Question

what is the difference between active and passive transport? passive uses no cell energy; active is high to low; passive is low to high; active uses no cell energy; passive uses cell energy; passive is high to low and uses no energy; active uses energy and is low to high

Explanation:

To determine the correct option, we recall the definitions of active and passive transport:

• Passive transport moves substances from an area of high concentration to low concentration (down the concentration gradient) and does not require cellular energy (e.g., diffusion, osmosis).
• Active transport moves substances from an area of low concentration to high concentration (against the concentration gradient) and requires cellular energy (usually ATP).

Now we analyze each option:

1. "Passive uses no cell energy" – This is only part of the difference, not the complete comparison between active and passive transport. Eliminate.
2. "Active is high to low; Passive is low to high" – This is incorrect. Active transport is low to high, passive is high to low. Eliminate.
3. "Active uses no cell energy; Passive uses cell energy" – This is the opposite of the correct definitions. Eliminate.
4. "Passive is high to low and uses no energy; Active uses energy and is low to high" – This matches the definitions of passive (high→low, no energy) and active (low→high, uses energy) transport.

Answer:

The correct option is the fourth one: "Passive is high to low and uses no energy; Active uses energy and is low to high"