B1.b Cell Transport - Chat GPT Flashcards
(19 cards)
What is diffusion?
The movement of particles from an area of high concentration to an area of low concentration (down the concentration gradient).
Is diffusion a passive or active process?
Passive.
Name 4 substances transported by diffusion.
Oxygen, carbon dioxide, urea, water.
What factors improve diffusion?
Large concentration difference, Good blood supply, Thin cells (short diffusion distance), Large surface area, High temperature, High SA:Volume ratio.
Why do single-celled organisms not need transport systems?
They have a large SA:V ratio, allowing sufficient diffusion.
Why do large organisms need transport systems?
They have a small SA:V ratio, so diffusion alone is insufficient.
How do lungs adapt for diffusion?
Thin alveoli and capillaries → short distance, Good blood flow → maintains gradient, Many alveoli → large surface area.
How do fish gills adapt for diffusion?
Many thin gill filaments → large surface area, Good blood flow + water flow → maintains gradient.
How do leaves adapt for gas exchange?
Thin structure → short diffusion distance, Large surface area, Stomata open and close to control gas exchange.
What is osmosis?
The diffusion of water from a dilute to a concentrated solution across a partially permeable membrane.
Is osmosis active or passive?
Passive.
What is the purpose of the potato osmosis experiment?
To observe how different concentrations affect water movement in and out of cells.
How is percentage change in mass calculated?
(New mass - Old mass) / Old mass × 100.
What does it mean when the graph line crosses the x-axis in the experiment?
The concentration inside the potato is equal to the solution; no net water movement.
What is active transport?
Movement of molecules from low to high concentration (against the gradient) using energy.
Is active transport passive or active?
Active (requires energy from mitochondria).
How do plants use active transport?
To absorb minerals from very dilute soil into root hair cells.
How do animals use active transport?
To absorb sugar molecules from the small intestine into the bloodstream.
