Proximity occurs when elements are in place together. This is usually perceived as a group. This is usually done when objects/person are in close proximity unity occurs. This is because the eye differentiate an object from the surrounding area. When objects are place without proximity. They will be perceived as separate objects. Proximity can be applied even if there is variation in sizes shape and even if it is radically different.
Answer: The most reason was that cell-to-cell communication and the different chemical compositions of the cell walls of plant, fungi, and bacteria restricts the intercellular communication to their own species.
