Maybe immune system and respiratory system
Human evolution known to be a process in which species adapt to certain conditions of life, and in the battle of life and death, they are forced to become stronger in order to survive in this world. Diseases have always been present during the evolution, acting themselves as a natural selectors - the weaker organisms get sick and die. Not just humans, but all species have to establish a great protecting mechanism in order to survive. That is how our bodies are built, to be able to withstand and survive in the conditions we live in, and that is why our immune system has to be taken care of.
Answer:
<h3>Carbon is released back into the atmosphere when organisms die, volcanoes erupt, fires blaze, fossil fuels are burned, and through a variety of other mechanisms. ... Humans play a major role in the carbon cycle through activities such as the burning of fossil fuels or land development.</h3>
Answer: <em>C.) Cnidarians</em>
molecules will gain energy, causing them to move faster and spread further from each other