Respiration is the process through which the cells of our body produce the energy that is required for performing many important tasks. Each cell of our body utilizes the food we eat by respiration to break down the glucose present in the food into usable energy.
pest - any unwanted and destructive insect or other animal that attacks food or crops or livestock etc.; he sprayed the garden to get rid of pests; many pests have developed resistance to the common pesticides.
The definition of systematic is something done according to a specific system, plan or method. An example of something that would be described as systematic is when weeds in a garden are all destroyed based on a carefully crafted weed-killing plan. forming or constituting a system. based on or involving a system.