The human respiratory system is a series of organs responsible for taking in oxygen and expelling carbon dioxide. The primary organs of the respiratory system are the lungs, which carry out this exchange of gases as we breathe. The circulatory system is made up of blood vessels that carry blood away from and towards the heart. Arteries carry blood away from the heart and veins carry blood back to the heart. The circulatory system carries oxygen, nutrients, and hormones to cells, and removes waste products, like carbon dioxide.
The respiratory system works directly with the circulatory system to provide oxygen to the body. Oxygen taken in from the respiratory system moves into blood vessels that then circulate oxygen-rich blood to tissues and cells.
Answer:
Over recent decades, evidence of increases in extreme weather events such as hurricanes, droughts, heat waves and heavy precipitation events has accumulated.
A control group is sort of the normal group. The group you aren't changing or messing with. It is to show what the species/experiment acts like on its own in response to something without you having to change it at all.
With an experimental group, you are changing something about the subject before putting it in the conditions it will need to respond to.
I don't entirely understand, but I know the control group is constant, unchanging. It sort of helps with distinguishing things. I have examples of experiments if that will help you understand what a control group is to answer the question. I also have a The Death Cure example if you have seen or read the book. I hope you do not fail this assignment, but even if I did not answer with an answer you were looking for, it could have helped you answer the question on your own.
I saw somewhere a similar question, though I was given the answer choices. If this is the answer you are looking for: variable(s).
Control groups don't use variables because you aren't changing them.
Answer: mutualism
Mutualism is a symbiotic relationship, between two organisms, living in close association with each other. In this relationship both the organisms gains benefit. Both organisms are dependent on each other for competing their life cycle.
The given situation is an example of mutualism because both the species are benefited for the relationship. Birds receive food from strawberries in turn birds disperse the seeds of strawberry to promote growth of more strawberry plants. Both organisms are interdependent on each other.