Answer:
Some body systems work together to complete a job. For example, the respiratory and circulatory systems work together to provide the body with oxygen and to rid the body of carbon dioxide. The lungs provide a place where oxygen can reach the blood and carbon dioxide can be removed from it. Some body systems share a common organ that performs more than one job.
Answer:
A closed system is a physical system that does not allow transfer of matter in or out of the system, though, in different contexts, such as physics, chemistry or engineering, the transfer of energy is or is not allowed.
Nitrogen is so important to plants because it is a major component of chlorophyll , or the compound by which plants use sunlight energy to produce sugars from water and carbon dioxide (photosynthesis). It is also a major component of amino acids, the building blocks of proteins for plants.
It's in the form of salt water. Hope this helps.
Definition : "Cellular respiration<span> is a set of metabolic reactions and processes that take place in the cells of organisms to convert biochemical energy from nutrients into adenosine triphosphate (ATP), and then release waste products."
Simplified : </span>Cellular respiration is used to take in food, then is used to create ATP. ATP is a chemical the cell uses for energy. This process is called aerobic respiration. The process uses oxygen, and has four stages known as Link reaction, glycolysis, the Krebs cycle, and the electron transport chain.
You might want to re-word the simple version a little, I worded it the best I could but I used information from wiki.
