Question

which type of transport moves substances against the concentration gradient and requires energy? osmosis diffusion active transport

Explanation:

To determine the correct answer, we analyze each option:

• Osmosis: It is the movement of water across a semi - permeable membrane along the concentration gradient (from high to low water concentration) and does not require energy. So it is not the correct answer.
• Diffusion: It is the movement of particles from an area of high concentration to an area of low concentration (along the concentration gradient) and does not require energy. So it is not the correct answer.
• Active transport: By definition, active transport is the process by which substances are moved across a cell membrane against the concentration gradient (from low to high concentration) and this process requires energy (usually in the form of ATP).

Answer:

active transport