diffusion and osmosis and active transport Flashcards
What is diffusion?
Diffusion is the transfer of energy from an area of high concentration to an area of low concentration. It travels down a concentration gradient and the larger the concentration gradient, the quicker the rate of reaction. It is a passive reaction mad it doesn’t require energy. Only takes place in liquids and gasses as particles only vibrate in solids.
Describe the gas exchange process between the alveoli and the bloodstream
CO2 is diffused from the bloodstream and back into the alveoli.
O2 is diffused from the alveoli into the bloodstream to be taken around the body.
What is osmosis?
The movement of WATER from a dilute (high water concentrated) solution to a concentrated (low water concentration) solution. It works down a concentration gradient and the particles are separated through a partially permeable membrane. It is a passive reaction.
What is a hypertonic solution?
Dilute/high water concentrated solution.
What is an isotonic solution?
A balanced solution
What is a hypotonic solution?
A concentrated/low water concentrated solution.
What happens when a cell is put in a hypertonic solution?
Because the solution has a low water concentration, the water leaves via osmosis meaning the cell wilts.
What happens when a cell is put into an isotonic solution?
The same amount of water both exits and leaves. The cell is in balance because the water concentration outside the cell is the same as inside the cell.
What happens when a cell is put into a hypotonic solution?
Because the solution is concentrated (low water concentration) that means that water enters the cell and the cell swells and eventually bursts.
Define a solute
Solid. A substance we put into a liquid. E.g. Sugar
Define a solution
What happens when the solute dissolves in the solvent.
Define concentration
How strong a solution is
Define a dilute solution
There are more water particles. High water concentration.
Define a concentrated solution
Less water particles. Low water concentration.
What happens to the cells inthe plant if there is enough water?
The plant cell vacuole is full of water and pushes against the cell wall. The cell wall stops the cell from bursting. We say that the cell is turgid.
Define a weak solution
More water particles/dilute
What happens when too much water enters or leaves a red blood cell?
In blood there is a substance called plasma. When it is placed in a CONCENTRATED SOLUTION (low water concentration), cells will shrivel as water is exiting the rbc to go into the solution. When the rbc is placed into distilled water (high water concentration) the cells swell as water is being added
Describe the potato experiment
We cut potato cylinders and tested the rate of osmosis. When the potato gained weight the solution it was put into had a higher water solution as compared to inside the potatoes cells. When the potato lost weight the solution it was put in had a lower water concentration as compared to inside the potato cells. The rate of reaction was quickest at both the biggest and lowest concentrations as the concentration gradient is largest.
What is active transport?
Active transport is a process that does require energy as it goes against the concentration gradient from an area of low concentration to an area of high concentration. Carrier proteins carry the molecules through. Carrier proteins require energy that comes from respiration that flea place in mitochondria.
Give an example of active transport.
If the concentration of minerals in the soil is greater than inside the plant itself. The minerals would move inside the cell via active transport.
What is the effect of temperature on active transport?
Because active transport requires proteins and enzymes are proteins. If we heat up the molecules the enzymes/carrier proteins will denature meaning the reaction will stop.
