The Circulatory System

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The Circulatory System is the transportation system for the body. The Circulatory System is responsible for the flow of blood. The function of the Circulatory System is to deliver chemicals to points in different parts of the body. More specifically, the Circulatory System permits blood to circulate and deliver nutrient molecules, oxygen and other gases, as well as hormones to and from cells. Along with removal of carbon dioxide, ammonia, and other metabolic wastes. 

The major organs of the Circulatory System are:

Heart: The purpose of the Heart is to pump blood throughout the body. This function supplies oxygen and nutrients to the tissues. As well as, removes carbon dioxide and other wastes.

Arteries: Arteries carry oxygenated blood from the heart to the tissues. However, pulmonary Arteries carry blood to the Lungs to be oxygenated.

Veins: After arteries carry blood out, the Veins are responsible for carrying this deoxygenated blood back to the heart. 

Although the Circulatory System touches all of the systems of the body in a way, this system mainly works with the Respiratory System, the Digestive System, the Endocrine System, and the Urinary System. The Circulatory System interacts with the Respiratory System to supply the body with oxygen and nutrients. The Circulatory System interacts with the Digestive System to get the absorbed nutrients distributed throughout the body. In addition, the Circulatory System carries chemical signals from the Endocrine System that control the speed of digestion. This example also proves one way the Circulatory System interacts with the Endocrine System as well. The Circulatory System is the transport system for endocrine information. As the endocrine chemicals and hormones must circulate through the body via blood vessels, the Circulatory System transports hormones (produced by the Endocrine System) through blood. Lastly, the Circulatory System works with the Urinary System because the Urinary System cleans the blood in the Circulatory System. Also, when blood travels back to the heart, it passes through the kidneys in the Urinary System. 

Analogy

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The Circulatory System resembles a UPS or delivery service for the body because:

• it delivers items to and from various places
• it carry and deliver items through transportation systems and pathways

The Circulatory System is like a UPS or delivery service for the body because both deliver items to and from various places. The Circulatory System delivers chemicals, such nutrient molecules, oxygen and other gases, and hormones to and from various parts of the body. These places include the heart, the lungs, different types of cells, and tissues. This is like how a UPS  or delivery service delivers goods to and from homes, stores, buildings, and factories. Another reason the circulatory system is like a UPS or delivery service for the body is that both carry items through transportation systems and pathways. The Circulatory System carry and deliver nutrients, oxygen and other gases, and hormones through red blood cells, arteries, and veins like how a UPS or delivery service carry and deliver different goods through trucks and streets/roads. 

Structure and Function

The structure of Arteries and Veins are very similar. Arteries and Veins both consist of the same three main layers. These layers are tunica intima, tunica media, and tunica enterna or tunica adventitia. The innermost layer of both Arteries and Veins is tunica intima. The middle layer of both Arteries and Veins is tunica media and the outermost layer of both Arteries and Veins is tunica enterna or tunica adventitia. In addition, both organs are shaped like thin or skinny pathways that are located throughout the body. I believe that because these organs are shaped like pathways, it is the reason they are responsible for carrying and delivering chemicals. Also, because both organs are located throughout the body, they can deliver chemicals and items to and from various parts of the body.

Sources:

http://www.biology4kids.com/files/systems_circulatory.html
http://www.livescience.com/27585-human-body-system-circulation-infographic.html