Transport Across Membranes Flashcards
(13 cards)
What is diffusion?
Diffusion is the movement of particles from an area of higher concentration to an area of lower concentration
What is an example of diffusion?
Oxygen moves from the blood into the cell by diffusion from higher concentration to lower
concentration
What are the four factors affecting diffusion?
-Temperature
-Surface area to volume ratio
-Distance
-Concentration gradient
How does temperature affect diffusion?
The higher the temperature, the faster the diffusion rate
How does surface area to volume ratio affect diffusion?
The larger the surface area to volume ratio, the faster the diffusion rate
How does distance affect diffusion?
The smaller the distance, the faster the diffusion rate
How does concentration gradient affect diffusion?
The steeper the concentration gradient, the faster the diffusion rate
What is osmosis?
Osmosis is the movement of water molecules from an area of higher water potential (concentration) to an area of lower
water potential (concentration) across a partially permeable membrane
What is water concentration?
The amount of water, as compared to other molecules, like solutes (sugars and salts)
What is active transport?
Active transport is the movement of molecules from lower to higher concentration, across a membrane, that requires energy from cellular respiration
Why does active transport require energy?
Active transport is an active process, where molecules move against the concentration gradient, which requires energy
Where does the energy for active transport come from?
The energy broken down by glucose in cellular respiration is stored in ATP, which takes energy to the parts of the cell that need it
How are root hair cells adapted for active transport?
-Lots of mitochondria, more energy from mitochondria
-Long root hair, large surface area for absorption
