Describe double circulation in human beings with the help of diagrams. Why is double circulation necessary? [5 MARKS]
Describe double circulation in human beings with the help of diagrams. Why is double circulation necessary? [5 MARKS]
Explanation: 2 Marks
Diagram: 3 Marks
1. In humans, blood flows through heart two times. This mechanism of blood flow is called as double circulation. Deoxygenated blood from all the body parts is collected and poured into the right side of the heart. From the heart, it goes to lungs for oxygenation. From the lungs, oxygenated blood comes again to heart, now to the left side of it. From the left side chambers, oxygenated blood is distributed to all body parts. Thus blood visits heart two times, once form body tissues and the second time from lungs. The circulation where blood is circulating through lungs is called as pulmonary circulation. When blood is flowing through body parts, it is called as systemic circulation.
2. Mammals and birds are warm-blooded. They maintain a constant internal temperature, despite the environment. Maintaining a constant internal temperature allows mammals and birds to carry-out body processes more efficiently, but it requires more energy. Without double circulation, the body tissues would not receive enough oxygen to maintain a constant temperature and would die.
Explanation: 2 Marks
Diagram: 3 Marks
1. In humans, blood flows through heart two times. This mechanism of blood flow is called as double circulation. Deoxygenated blood from all the body parts is collected and poured into the right side of the heart. From the heart, it goes to lungs for oxygenation. From the lungs, oxygenated blood comes again to heart, now to the left side of it. From the left side chambers, oxygenated blood is distributed to all body parts. Thus blood visits heart two times, once form body tissues and the second time from lungs. The circulation where blood is circulating through lungs is called as pulmonary circulation. When blood is flowing through body parts, it is called as systemic circulation.
2. Mammals and birds are warm-blooded. They maintain a constant internal temperature, despite the environment. Maintaining a constant internal temperature allows mammals and birds to carry-out body processes more efficiently, but it requires more energy. Without double circulation, the body tissues would not receive enough oxygen to maintain a constant temperature and would die.
