This condition is known as lymphadema. After surgical removal of chain lymph nodes has occurred, the excess of lymph fluids in the lymph vessels might not find its way to the bloodstream as a result of being blocked or other reasons, and hence localized swelling in that area occurs as a result of addition of the fluids. In most cases, lymphadema affects only a single arm or leg, and is commonly brought on by cancer treatment that involves damging or removing lymph nodes.
When food is digested, the food is broken down into Glucose, which can get into the bloodstream through the small intestines. It travels around the body in the bloods plasma and is then diffused into the body's cells through the capillaries. Once the Glucose is in the body cells, it can be used for respiration.
The breathing system is used in respiration because we need it to respire aerobically, so that our body gets all the vital oxygen it needs. When we breathe, oxygen is stored in the alveoli in the lungs. From there, it can be diffused into the bloodstream, to be used for respiration.
The products of aerobic respiration is Carbon Dioxide and Water. The Water leaves the body as sweat or waste such as urine. The Carbon Dioxide is carried through the blood to our lungs where we can breathe it out. Where as in anaerobic respiration, the product is Lactic Acid. This ends up being broken by oxygen after exercise (oxygen debt) and is also turned into Carbon Dioxide and Water.
"B.) profound social and economic changes occurred" because when the industrial revolution happened a lot of how we make stuff was changed, by factories, and because of this new jobs where created. This gave people money and thus social and economic changes happened.