_______ plays an important role in maintaining a person’s _______ and sustaining life. As you already learned, blood carries oxygen and nutrients through the body, while also removing carbon dioxide and waste. _______ a person’s body temperature, similar to how a _______ regulates the temperature in a room. Blood also protects the body against infection.
Because of blood’s vital role in the _______ , many people donate blood to organizations such as the American Red Cross. In fact, one pint of donated blood can save up to three lives. For this reason, people who donate blood are actually giving the gift of life.
Blood is made up of both _______ parts (Figure 2.11). The liquid part of blood is called plasma. Plasma makes up at least half of blood's content. It is responsible for carrying all parts of blood throughout the body.The solid parts of blood consist of _______ blood cells, _______ blood cells, and platelets.
Red blood cells make up one-half the blood’s volume. Red blood cells contain a red substance called hemoglobin, which can carry and _______ . As a result, red blood cells transport oxygen throughout the body.
_______ cells move through the blood and live in various organs of the body. They help defend the body against infections.
Platelets are responsible for blood clotting. _______ stops blood from flowing outside the wall of a blood vessel. This action helps prevent blood loss when blood vessels are injured.