Answer the following question given this paragraph: Figure 39.21 Individuals with sickle cell anemia have crescent-shaped red blood cells. (credit: modification of work by Ed Uthman; scale-bar data from Matt Russell). Q: Individuals with sickle cell anemia have crescent-shaped what? Choices: - glial cells - white blood cells - nerve cells - red blood cells A:
red blood cells

Answer the following question given this paragraph: Cardiac muscle is also an involuntary muscle, found only in the heart. The cardiac muscle fibers all contract together, generating enough force to push blood throughout the body. What would happen if this muscle was under conscious or voluntary control?. Q: What involuntary muscle is found only in the heart? Choices: - physiological muscle - respiratory muscle - digestive muscle - cardiac muscle A:
cardiac muscle

Answer the following question given this paragraph: Based on their molar masses, hydrogen is the lightest molecule, and oxygen is the heaviest. Because all three volumes are the same, each balloon contains the same number of gas molecules. Therefore, the hydrogen balloon will have the lowest mass, and the oxygen balloon will have the highest. Q: What is the lightest molecule? Choices: - oxygen - helium - silicon - hydrogen A:
hydrogen