Final answer:
The average adult has 4.7 to 5.7 liters of blood composed of blood plasma, red and white blood cells, and platelets. Plasma is the largest part by volume, with water being its main constituent. Blood is vital for various bodily functions, including defense, transportation, and regulation.
Step-by-step explanation:
The average adult body contains between 4.7 and 5.7 liters (5-6 quarts) of blood, which constitutes approximately 8 percent of adult body weight. Adult males typically have an average volume of about 5 to 6 liters of blood, while females average 4-5 liters. The main components of blood include blood plasma, red blood cells (erythrocytes), white blood cells (leukocytes), and platelets. Blood plasma, making up more than half of the blood's volume, consists of about 92 percent water, proteins, and hundreds of other dissolved substances. Red blood cells contain hemoglobin and are responsible for delivering oxygen throughout the body. White blood cells are essential for the immune response, and platelets play a critical role in blood clotting. In summary, blood is a multifunctional fluid that is crucial for transporting oxygen, nutrients, hormones, and waste, providing defense against pathogens, and maintaining homeostasis within the body.