osmosis and diffusion experiment
Experiment 1
Background
Diffusion is a process, in relation to the spontaneous movement of molecules from an area of high concentration, to an area of low concentration down a concentration gradient.
It is a type of passive transport method, that requires no cellular energy (ATP). This movement occurs, until a state of equilibrium has been established on both sides of the membrane. The diffusion of molecules happens at cellular level, through a cell membrane via the pores. The cell membrane is a layer that’s located between the cell wall and the cytoplasm (containing organelles of the cell). The cell membrane, contains a phospholipid bilayer that is selectively permeable, which means that it will only permit certain molecules to pass through its pores. An example of diffusion occurs for the transport of o2 and co2 via the alveoli into the blood and blood to the alveoli.
A glucose molecule, is a monosaccharide, composing of a single monomer and starch is a polysaccharide, a complex carbohydrate that is composed of a long chain of several glucose molecules. Due to the structural content of these molecules a hypothesis can be made in regards to the following experiment.
Hypothesis: Small molecules will only be able to diffuse through the cell membrane.
AIM: To investigate selective permeability against starch and glucose molecules.
APPARATUS:
4 Test Tubes
Cellophane Tubing
Elastic Band
2 beakers
Glucose solution
Starch solution
2 Syringes
Pipette
Hot Plate.
Test Tube rack.
Benedict’s Solution
Iodine Solution
Safety Aspects
Safety aspects that need to be considered during the experiment are to provide caution whilst handling benedict’s solution as it can be caustic to the skin and eyes. As a safety measure wear a lab coat, gloves and protective goggles at all times .
Handle glass ware with care to minimise breakage.
Follow general lab practice.
METHOD
The apparatus was
Background
Diffusion is a process, in relation to the spontaneous movement of molecules from an area of high concentration, to an area of low concentration down a concentration gradient.
It is a type of passive transport method, that requires no cellular energy (ATP). This movement occurs, until a state of equilibrium has been established on both sides of the membrane. The diffusion of molecules happens at cellular level, through a cell membrane via the pores. The cell membrane is a layer that’s located between the cell wall and the cytoplasm (containing organelles of the cell). The cell membrane, contains a phospholipid bilayer that is selectively permeable, which means that it will only permit certain molecules to pass through its pores. An example of diffusion occurs for the transport of o2 and co2 via the alveoli into the blood and blood to the alveoli.
A glucose molecule, is a monosaccharide, composing of a single monomer and starch is a polysaccharide, a complex carbohydrate that is composed of a long chain of several glucose molecules. Due to the structural content of these molecules a hypothesis can be made in regards to the following experiment.
Hypothesis: Small molecules will only be able to diffuse through the cell membrane.
AIM: To investigate selective permeability against starch and glucose molecules.
APPARATUS:
4 Test Tubes
Cellophane Tubing
Elastic Band
2 beakers
Glucose solution
Starch solution
2 Syringes
Pipette
Hot Plate.
Test Tube rack.
Benedict’s Solution
Iodine Solution
Safety Aspects
Safety aspects that need to be considered during the experiment are to provide caution whilst handling benedict’s solution as it can be caustic to the skin and eyes. As a safety measure wear a lab coat, gloves and protective goggles at all times .
Handle glass ware with care to minimise breakage.
Follow general lab practice.
METHOD
The apparatus was