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• The eyepiece always magnifies things by 10 x
• the objective lens magnification is often x5,x10 or x20
• we multiply the eyepiece magnification by the objective lens magnification
• A microscope makes an object look bigger than it actually is.
• animal and plant cells have similar structures. But plant cells have some extra features
• Every cell has a thin cell membrane surrounding it
• the cell membrane acts as a barrier.
• cell membrane controls what substances can enter or leave the cell
• every cell is filled with cytoplasm
• cytoplasm is a watery gel with many useful substances dissolved in it.
• every cell has a nucleus somewhere in the cytoplasm
• The nucleus directs the cell’s activity
• A nucleus had a set of instructions called genes