This deep dive covers Factors Affecting Transport Rate within Cell Transport for GCSE Biology. Diffusion, osmosis, active transport, factors affecting transport, surface area to volume ratio, and practical investigations It is section 4 of 19 in this topic. Use this deep dive to connect the idea to the wider topic before moving on to questions and flashcards.

🎯 Factors Affecting Transport Rate

📊 Concentration Gradient

The steeper the gradient (bigger difference in concentration), the faster the rate of diffusion.

Example: Oxygen diffuses faster from lungs to blood when the difference is greater

🌡️ Temperature

Higher temperature = more kinetic energy = faster particle movement = faster diffusion.

Example: Perfume spreads faster on a hot day

📏 Surface Area

Larger surface area provides more space for particles to cross = faster diffusion.

Example: Alveoli have millions of tiny air sacs to maximize surface area

📐 Distance

Shorter diffusion distance = faster transport. Thicker barriers slow down diffusion.

Example: Alveoli walls are only one cell thick

Practice questions for Cell Transport

Which statement best describes diffusion?

A. The movement of particles from a region of low concentration to high concentration
B. The net movement of particles from a region of high concentration to low concentration
C. The movement of water molecules through a partially permeable membrane
D. The movement of particles using energy from respiration

1 markfoundation

Explain how osmosis causes a plant cell to become plasmolysed when placed in a concentrated sugar solution.

3 marksstandard

Quick recall flashcards

Define diffusion

The movement of particles from an area of high concentration to an area of low concentration down a concentration gradient. No energy is required (passive process).

Define osmosis

The movement of water molecules from an area of high water concentration (low solute concentration) to an area of low water concentration (high solute concentration) through a semi-permeable membrane.

Factors Affecting Transport Rate