DEFENCE NANOSYSTEMS FOR PLANTS AND ANIMALS

In nature, we can find a variety of systems by which plants and animals are defending against dangers coming from their surroundings. The aim of this contribution is to show three different types of nanostructures, which are one, two or three-dimensional and show their function in defense of objects in nature. The first type is nanoparticles. In specific types of plants, when they are growing they make primary nanoparticles which are made of silicon dioxide with a size from one till tens of nanometres. These structures then form a bigger globular formation. Moreover, these formations make up layers, which serve as a compact barrier against microorganisms. The second type of nanostructures has a prolonged shape with a diameter size of tens of nanometres and a length of hundreds of nanometres. It could be found on plant surfaces. These structures have wax characteristics which allow them to be superhydrophobic. From these kinds of surfaces even dirt can be washed away, as well as pathogens which stick to drops of water. The third type of nanostructure is a three-dimensional nanoformation in a conical shape, which can be found on the wings of cicada. The ratio of these formations is approximately 150 nanometres at the base and 30 nanometres at the top, with a height of 300 nanometres. These nanocones have the ability to disturb cell walls of bacteria which are sticking to it. The breaching of these cell walls is caused by physical-mechanical processes without using chemical substances.