Circulation in Animals

Open and Closed Circulatory Systems

    Many animals have a open or closed circulatory system. Open and closed circulatory system shares three basic components: blood, blood vessels, and and a heart. Blood is a circulatory fluid in our body, Blood vessels are a set of tubes where the blood moves throughout our body, and the heart is a pump. The heart is an key organ because is keeps blood flowing throughout the whole body. The heart uses metabolic energy to elevate the hydrostatic pressure. The blood pressure is the motive force for fluid movement. 
    In an open circulatory system organs are covered(surrounded) with blood (blood is the body fluid in this system). When blood is regulated throughout our body chemical exchange happens within body cells and the blood. Body movements that squeeze the sinus help circulate blood. 
In a closed circulatory system blood is separated from body fluid. One main vessel(kinda like a heart) pumps blood into smaller tinier branches throughout the body. Nutrients and materials are exchanged between blood and interstitial through diffusion. 
Animals with open circulatory systems use less energy overall compared to an animal with a closed circulatory system. Benefits of a closed circulatory animal is that since they have a higher blood pressure it is easier to transport circulatory fluids throughout the body. Closed circulatory systems are most highly developed in vertebrates.

Vertebrate Circulation

    Closed circulatory system is the same thing as the cardiovascular system. We all have an heart with one or two chambers known as atria that receive blood and one or two other chambers known as ventricles that pump blood out of the heart. There are three main kinds of blood vessels; arteries, veins, and capillaries. Arteries carry blood away from the heart and to the organs in the body, which branch into smaller vessels known as arterioles. Capillary beds are thin tubes that go through each tissue. Chemical exchange occurs through diffusion. Arteries carry blood from the heart to capillaries and veins return blood from the capillaries to the heart. 

    Fishes Amphibians Reptiles Mammals and Birds

    Fishes have a two chambered heart one ventricle and one atrium. Gill circulation is when the blood pumped from the ventricle goes to the gill where oxygen is obtained and carbon dioxide is release. Systemic circulation is when oxygen rich blood is sent away from the heart and into the body. 
    Amphibians have a three chambered heart with two atria and one ventricle. Blood is pumped into the pulmocutaneous circuit and they systemic circuit. The pulmocutaneous circuit pumps blood into the capillaries and oxygenated blood is sent into the system. Double circulation is when blood is flown to the organs and then pumped a second time to the organs after it loses pressure, at a reduced pressure.
    Reptiles have double circulation, pulmonary circuit and systemic circulation. Reptiles have a three chambered heart with the ventricle partially divided by a septum causing less mixing of oxygen rich and poor blood. All reptiles have arterial valves that allows them to divert most of their blood from the pulmonary circuit to the systemic circuit.
    Mammals and Birds