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  • Solute Concentration External To The Cell
    1,562 words
    The aim of this experiment is to investigate the movement of water into and out of plant cells by osmosis. The cells chosen for study will be taken from potato tubers as they provide a ready supply of uniform material. Any substance dissolved in water is called a solute; a solvent is a liquid that is able to dissolve another substance, called a solute, to form a solution. The water content of plants varies depending on environmental conditions. In Land plants this water plays a vital role in the...
  • Substances Across The Cell Membrane
    931 words
    Homeostasis is essential to the cell's survival. The cell membrane is responsible for homeostasis. The membrane has a selective permeability which means what moves in and out of the cell is regulated. Amino acids, sugars, oxygen, sodium, and potassium are examples of substances that enter the cell. Waste products and carbon dioxide are removed from the cell. All of these substances cross the membrane in a variety of ways. From diffusion and osmosis, to active transport the traffic through the ce...
  • Reaction Fe 3 Scn Fescn 2
    442 words
    Work to be done: By experiments find out how chemical equilibria works. Chemicals and apparatus: Two beakers Five test-tubes Kaliumtiocyanat, KSCN 0.002 M Kaliumtiocyanatsolution, KSCN + H 2 O Dinatriumfosfat, Na 2 HPO 4 0.002 M Iron ( ) nitratesolution, FeNO 3 0.2 M Silvernitratesolution, AgNO 3 Lab: Lab 1 One test-tubes is filled half of distilled water (A) and another with kaliumtiocyanatsolution (B). Both solutions are colorless. Solution (B) contains SCN-. I add five drops of iron ( ) nitra...
  • Nacl Solution At 0 2 Molar Concentration
    1,454 words
    Introduction Knowing that osmosis (a diffusion of water) will occur across a semi-permeable membrane whenever there is a difference between the water concentrations on the two sides of the membrane, and knowing that when this happens to cells they will either become turgid if water flows into them, or plasmolysed if water flows out of them, and thus change their volume, we want to test the hypothesis that: If the concentration of a solution into which a cylinder of potato is placed is greater th...
  • Absorbency Values Of The Betacyanin Solutions
    1,194 words
    Measuring the Absorption of 525 nm Light into Stock and Leaked Betacyanin Solutions Created from Beet Root Discs Which Vary in Concentration Introduction: The Pigment Betacyanin is a pigment located in the large central vacuole of a beet cell. These vacuoles are surrounded by a membrane called the tonoplast and are located in the cytosol of the cell. Surrounding the cell is another membrane called the plasma membrane. Under normal conditions these two membranes remain intact. However when the me...
  • Solution The Faster The Bead
    852 words
    Biology Coursework Alginate beads experiment Aim: To investigate the effects of substrate concentration on an enzyme reaction. Background: An enzyme is a protein formed in living cells and assisting chemical processes. Catalyst is a substance that speeds up reactions. The alginate beads are made of alginate and potato juice. The alginate bead experiment works because of oxygen bubbles which stick to the bead which makes the bead rise soon after dropping it into hydrogen peroxide. Hydrogen peroxi...
  • Osmotic Potential Of The Solution
    510 words
    Introduction The presence of solutes in water causes the osmotic potential to decrease and it reduces the free energy of water. This is because water molecules will tend to bind to the solutes rather than moving freely and away from the solution. If cells are surrounded by a solution that has an osmotic potential more negative (lower) than that inside the cell, water will move from inside the cell (higher water potential) to the outside solution (lower water potential) by osmosis. This water los...
  • Potassium Thiocyanate And Iron III Chloride
    1,089 words
    Experiment 36 Disturbing Equilibrium Aim: To observe the effect of a change in conditions on a system at equilibrium and explain the effects observed through Le Ch^atelier's principle. Equipment: 5 medium test tubes 1 test-tube rack 1 100-mL beaker 1 250 mL beaker 1 dropper pipet 1 spatula 1 50-mL graduated cylinder 1 white card, to record Materials: Saturated potassium nitrate solution, KNO 3 0.1 M Iron ( ) chloride, FeCl 3 0.1 M Potassium thiocyanate, KSCN Potassium chloride crystals, KCl Pota...
  • Results For The Sucrose Concentrations
    646 words
    The results of this lab where quite what one would expect. The lower the mol age of the sucrose concentration, the more the potato grew in mass. For an extreme example take the final results of the distilled water and the 1 M of sucrose solution. The % in weight change for the 1 M of sucrose concentration was -12.5 which was over all the highest change, and the least mass left in the potato cores. The opposite was true for the potato cores in the distilled water. In the end they grew by 5.7%, th...
  • Concentrations Of 0 1
    1,072 words
    Aim To find out the lowest concentration of copper (II) sulphate solution that brings about full denaturation of egg albumen. Background Information Denaturation is the breakdown of the bonds forming the quaternary, tertiary and secondary structures of proteins and nucleic acids. Changes in the shape of a protein lead to its inactivation. Albumen is a globular protein, which contains carbon, oxygen, nitrogen and hydrogen. Proteins usually contain sulphur too. Globular proteins are composed of a ...
  • 10 Cm 3 Of A Concentrated Solution
    442 words
    Biology coursework Investigation of osmosis in potato tissue AIM. To investigate the effects that occur by osmosis on potato tissue Hypothesis I believe that the higher the concentration of sugar solution, the mass of the potato decreases yet I believe that after 0.4 the mass decreases. Scientific knowledge A biochemical process in living cells, that occurs with the movement of water. It can be deemed as the movement of water from a high concentration to a lower concentration, the diffusion down...
  • 100 Ml Test Tubes
    355 words
    Objective: Visually determine the molar concentration of a dichromate ion in an unknown solution of Cr 2 O 7 using color bracketing. Background: Many ions impart a color to the aqueous solutions in which they are dissolved. The intensity of the color is directly proportional to the concentration of the ion. When dissolved in water, the dichromate ion imparts a faint yellow color to the solution. The concentration may be determined by visual color comparison to a set of prepared standard solution...

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