Practical: Using a Light Microscope Many biological structures are too small to be seen by the naked eye Optical microscopes are an invaluable tool for scientists as they allow for tissues, cells a...
Practical: Investigating the Rate of Transpiration Using a potometer Air movement, humidity, temperature and light intensity all have an effect on the rate at which transpiration occurs The table b...
Serial Dilutions Serial dilutions are created by taking a series of dilutions of a stock solution. The concentration decreases by the same quantity between each test tube They can either be ‘doubli...
Chromatography Chromatography is a technique that can be used to separate a mixture into its individual components Chromatography relies on differences in the solubility of the different chemicals ...
Biochemical Tests: Proteins The Biuret test can be carried out quickly and easily in a lab to determine if a sample contains proteins Biuret ‘reagent’ contains an alkali and copper (II) sulfate whi...
Biochemical Tests: Lipids Identifying biological molecules Different qualitative reagents can be used to identfy the presence of biological molecules in samples Ethanol is used to identify lipids B...
Biochemical Tests: Reducing Sugars & Starch Benedict’s solution can be used to carry out a semi-quantitative test on a reducing sugar solution to determine the concentration of reducing sugar p...
Practical: Factors Affecting Membrane Structure & Permeability The permeability of cell membranes is affected by different factors or conditions, such as: Temperature Solvent concentration &nbs...
Practical: Investigating Water Potential Practical 1: Investigating water potential using potato cylinders It is possible to investigate the effects of immersing plant tissue in solutions of differ...
