A piece of papaya was squeezed between the microscope slide and cover glass. The sample was observed in polarized light (see Simple Polarization Microscopy). The cell walls (made of cellulose) are clearly visible using this method.
Carica papaya, also referred to as the “big melon”, is a native of tropical Americas (southern Mexico, Central America and northern South America). Papayas are not only used as food: They contain the enzyme Papain, which is a protease and able to break down proteins. It is used in biotechnology. Papain ointment can also be used to treat cuts, rashes, stings and burns.