The purpose of experiment A of exercise 1, is so that the students can observe Brownian movement. Brownian movement is the random movement of particles in a gas or liquid caused by the collision of molecules of the medium. This movement should be observed in the carmine slides by the irregular motion of the red pigment particles in the water solution.
In experiment B of exercise 1,the students will investigate the process of osmosis and diffusion in a model membrane system and the effect of solute concentration on water potential, the force created by both physical pressure and solute concentration, as it relates to living plant tissues. Diffusion is the passive movement of molecules or particles from a region of high concentration to an area of low concentration. Particularly, osmosis, a special type of diffusion, is the diffusion of a solvent, usually water molecules, through a semi permeable membrane, which is a membrane that is only permeable to certain molecules, from an area of low solute …show more content…
They will do this by placing a solution of glucose and starch inside a bag of dialysis tubing. The tubing will then be placed in a beaker filled with distilled water and I2Kl. After 30 minutes, the students will test for glucose with benedict’s solution. If a solution of 4 pipettesful of 30% glucose and 4 pipettesful of starch solution, in a dialysis bag, is placed in a beaker containing distilled water and I2Kl, then the glucose molecules will diffuse out of the dialysis bag until it reaches dynamic equilibrium. However, starch will not diffuse out of the dialysis bag because its molecules are larger than the pores of the bag. Also, I2Kl will diffuse into the bag making the solution inside the dialysis bag purple in
In experiment B of exercise 1,the students will investigate the process of osmosis and diffusion in a model membrane system and the effect of solute concentration on water potential, the force created by both physical pressure and solute concentration, as it relates to living plant tissues. Diffusion is the passive movement of molecules or particles from a region of high concentration to an area of low concentration. Particularly, osmosis, a special type of diffusion, is the diffusion of a solvent, usually water molecules, through a semi permeable membrane, which is a membrane that is only permeable to certain molecules, from an area of low solute …show more content…
They will do this by placing a solution of glucose and starch inside a bag of dialysis tubing. The tubing will then be placed in a beaker filled with distilled water and I2Kl. After 30 minutes, the students will test for glucose with benedict’s solution. If a solution of 4 pipettesful of 30% glucose and 4 pipettesful of starch solution, in a dialysis bag, is placed in a beaker containing distilled water and I2Kl, then the glucose molecules will diffuse out of the dialysis bag until it reaches dynamic equilibrium. However, starch will not diffuse out of the dialysis bag because its molecules are larger than the pores of the bag. Also, I2Kl will diffuse into the bag making the solution inside the dialysis bag purple in