The respiratory system, urinary system, and digestive system make up the three maintenance systems, which aid the body by keeping the conditions of its fluids stable and constant. Each system keeps the body stable by adding and/or removing substances from the body.
The respiratory system uses the trachea, lungs, tubes such as the bronchi, bronchioles, and alveoli, and the diaphragm to transport gases into, throughout, and out of the body to maintain a stable internal environment. The respiratory functions to supply an animal with the oxygen it needs to live while ridding the body of carbon dioxide, which is vital to the body’s homeostasis. The respiratory system gets oxygen into the body and carbon dioxide out of the body by the breathing function, …show more content…
Most animals have diverse digestive tracts, which are modified according to the means of obtaining food and diet of the animal, but they all perform a set of functions needed to provide nutrition. For example, hydras, planarians, and earthworms have a digestive tubular tract where one end of the tube is the entrance for food and the other end is the exit for waste; other more complex animals have to go through several stomach compartments, ruminants, as their food digests, until it exits the body as waste. Either way, all bodies must first ingest food by mouth, a primarily mechanical process. Food in the mouth is broken down by the enzyme salivary amylase, in saliva (and chewing, if the animal can), and is then sent down the pharynx and the esophagus (the tube that connects the pharynx and stomach), and into the stomach. Within an animal’s stomach (or stomachs, or gizzard after being stored in an organ like a crop), the partial chemical breakdown of food occurs. Food is broken down when the stomach churns and mixes the food with stomach acid, often containing hydrochloric acid and released by parietal cells, pepsin, which digest protein and are released by chief cells, protozoans, and bacteria (in the case of ruminant animals). Next, the food is passed on to the small intestine where it is digested further by pancreatic juice and bile from the pancreas and liver, respectively (both of which are accessory organs, and not a part of the digestive system, technically) that digest starch (pancreatic amylase), fat (lipase), and protein (trypsin). In the small intestine, starches in the broken down form of glucose and proteins broken down into amino acids are allowed to cross the small intestine’s membrane and enter the blood capillaries, where they will be put to use as energy makers. Digested fats become glycerols and fatty acids that are packaged and sent
The respiratory system uses the trachea, lungs, tubes such as the bronchi, bronchioles, and alveoli, and the diaphragm to transport gases into, throughout, and out of the body to maintain a stable internal environment. The respiratory functions to supply an animal with the oxygen it needs to live while ridding the body of carbon dioxide, which is vital to the body’s homeostasis. The respiratory system gets oxygen into the body and carbon dioxide out of the body by the breathing function, …show more content…
Most animals have diverse digestive tracts, which are modified according to the means of obtaining food and diet of the animal, but they all perform a set of functions needed to provide nutrition. For example, hydras, planarians, and earthworms have a digestive tubular tract where one end of the tube is the entrance for food and the other end is the exit for waste; other more complex animals have to go through several stomach compartments, ruminants, as their food digests, until it exits the body as waste. Either way, all bodies must first ingest food by mouth, a primarily mechanical process. Food in the mouth is broken down by the enzyme salivary amylase, in saliva (and chewing, if the animal can), and is then sent down the pharynx and the esophagus (the tube that connects the pharynx and stomach), and into the stomach. Within an animal’s stomach (or stomachs, or gizzard after being stored in an organ like a crop), the partial chemical breakdown of food occurs. Food is broken down when the stomach churns and mixes the food with stomach acid, often containing hydrochloric acid and released by parietal cells, pepsin, which digest protein and are released by chief cells, protozoans, and bacteria (in the case of ruminant animals). Next, the food is passed on to the small intestine where it is digested further by pancreatic juice and bile from the pancreas and liver, respectively (both of which are accessory organs, and not a part of the digestive system, technically) that digest starch (pancreatic amylase), fat (lipase), and protein (trypsin). In the small intestine, starches in the broken down form of glucose and proteins broken down into amino acids are allowed to cross the small intestine’s membrane and enter the blood capillaries, where they will be put to use as energy makers. Digested fats become glycerols and fatty acids that are packaged and sent