1 1 The diagram shows the double circulation of a mammal. The arrows indicate the movement of oxygen and carbon dioxide in and out of the blood. Explain the advantages of a double circulation. Double circulation allows oxygenated and deoxygenated blood to stay separated, making sure .................................................................................................................................................. there is efficient oxygen delivery to tissues. Different pressure levels regarding different blood .................................................................................................................................................. vessels allow for better optimization of the blood systems. .................................................................................................................................................. .................................................................................................................................................. .................................................................................................................................................. .................................................................................................................................................. .................................................................................................................................................. .................................................................................................................................................. .................................................................................................................................................. [4] [Total: 4] 2 2 The diagram shows the double circulation of a mammal. The arrows indicate the movement of oxygen and carbon dioxide in and out of the blood. Describe the evidence shown in the diagram that the mammal has a double circulatory system. The diagram shows blood vessels traveling separately to the lungs and to the rest of the .................................................................................................................................................. body. This shows two systems of circulation, and a double circulatory system. .................................................................................................................................................. .................................................................................................................................................. .................................................................................................................................................. .................................................................................................................................................. [2] [Total: 2] 3 3 Mammals have a double circulation. The diagram shows a section through the heart of a mammal. The arrows show the direction of blood flow through the heart and blood vessels. D is a vein. State the name of this vein and describe its structure. Vena cava name ........................................................................................................................................ The vena cava is a large vein with thin walls that carries description of structure ............................................................................................................. deoxygenated blood back to the right atrium of the heart. .................................................................................................................................................. The walls of the vein are less muscular than arteries, and it has .................................................................................................................................................. valves to prevent backflow. .................................................................................................................................................. .................................................................................................................................................. .................................................................................................................................................. [3] [Total: 3] 4 4 The human circulatory system contains blood vessels. The diagram shows some names of blood vessels and organs. The boxes on the left show the names of some blood vessels that deliver blood to organs. The boxes on the right show the names of some organs that receive blood. Draw straight lines from each blood vessel to the organ that it delivers blood to. Draw four straight lines. blood vessel that delivers blood organ receiving blood pulmonary artery heart pulmonary vein kidney renal artery lungs vena cava [4] [Total: 4] 5 5 The photomicrograph is of human blood. Use the information in the photomicrograph to complete the table by stating one function for each cell. identifying letter in photomicrograph A function Carries oxygen throughout the blood vessels to tissues throughout the body Defends the body against infections and creates antibodies B [2] [Total: 2]
