What is a depression slide?
its when ure sad and u fall down.
Explain why you could not use an oak leaf in this investigation. ?
Cells in an onion can be peeled into very thin layers, and human cheek cells can be swabbed from your mouth. Both of these are easy to visualize on a light microscope since the light will pass right through them. Oak leaves are too thick and will block the light, preventing you from seeing much of anything useful under the microscope.
Immersion oil is used to increase the resolution because?
In light microscopy, oil immersion is a technique used to increase the resolution of a microscope. This is achieved by immersing both the objective lens and the specimen in a transparent oil of high refractive index, thereby increasing the numerical aperture of the objective lens. Immersion oils are transparent oils that have specific optical and viscosity characteristics necessary for use in microscopy. Typical oils used have an index of refraction around 1.515. An oil immersion objective is an objective lens specially designed to be used in this way. Many condensers also give optimal resolution when the condenser lens is immersed in oil. So in short: refractive index
Why is saline solution used for experiments?
Because if you used pure water the cheek cells would burst due to osmotic pressure. This is called osmolysis. The plasma membrane is permeable to water and the interior of the cell is salty. Pure water would pass through the plasma membrane leading to excess pressure.