03) Movement into and out of cells * Flashcards
1.1. Describe diffusion
The net movement of particles from a region of their higher concentration to a region of their lower concentration down a concentration gradient, as a result of their random movement
1.2. Where does the energy for diffusion come from?
The kinetic energy of random movement of molecules and ions
1.3. How do some substances move into and out of cells?
By diffusion through the cell membrane
1.4. Describe the importance of diffusion of gases and solutes in living organisms
1.5. Investigate the factors that influence diffusion, limited to: surface area, temperature, concentration gradient and distance
Surface area:
Temperature:
Concentration gradient:
Distance:
2.1. Describe the role of water with reference to digestion, excretion and transport
A solvent in organisms
2.2/3. How does water diffuse (into and out of cells) through partially permeable membranes?
Osmosis
2.6. How are plants supported?
By the pressure of water inside the cells pressing outwards on the cell wall
2.7. Describe osmosis
The net movement of water molecules from a region of higher water potential (dilute solution) to a region of lower water potential (concentrated solution), through a partially permeable membrane
2.8. Explain the effects on plant cells of immersing them in solutions of different concentrations by using the terms: turgid, turgor pressure, plasmolysis, flaccid
2.9. Explain the importance of water potential and osmosis in the uptake and loss of water by organisms
3.1. Describe active transport
The movement of particles through a cell membrane from a region of lower concentration to a region of higher concentration against a concentration gradient, using energy from respiration
3.2. Explain the importance of active transport
It is a process for movement of molecules or ions across membranes, including ion uptake by root hairs
3.3. What do protein carriers move during active transport and where do they move them to?
Molecules or ions across a membrane
