Cell Transport Flashcards
What is diffusion?
Movement of particles from an area of high concentration to an area of low concentration which doesn’t require energy
Name 3 factors that affect the rate of diffusion
Concentration gradient, temp, membrane surface area
How are villi adapted for exchanging substances?
Long and thin- increases surface area
One cell thick membrane- short diffusion distance
Good blood supply- maintains a steep concentration gradient
How are the lungs adapted for efficient gas exchange?
Alveoli- large surface area
Moist membranes- increases rate of diffusion
Good blood supply- maintains a steep concentration gradient
How are fish gills adapted for efficient gas exchange?
Large surface area for gases to diffuse across
Thin layer of cells- short diffusion distance
What is osmosis?
The movement of water from a dilute to concentrated solution through a partially permeable membrane
Give one example of osmosis in a plant
Water moves from the soil into the root hair cell
What is active transport?
Movement of particles against a concentration gradient from a dilute to a concentrated solution using energy from respiration
Why is active transport needed in plant roots?
Concentration of mineral ions in the soil is lower than inside the root hair cells
What is the purpose of active transport in the small intenstine?
Sugars can be absorbed into the blood when the concentration of sugar in the small intestine is lower than the concentration of sugar in the blood
