Chapter 18 of Class 11 Biology, titled Body Fluids and Circulation, explains the structure and function of the human circulatory system. It covers essential topics such as blood circulation, the heart’s structure, and the role of blood vessels, including arteries and veins. The chapter also explores the cardiac cycle, blood pressure, and the lymphatic system. Students will learn how body fluids circulate through the body, ensuring nutrient and oxygen transport, and maintaining overall homeostasis. These solutions simplify the key processes for clearer understanding and exam preparation.