CIRCULATORY

• What is the primary function of the circulatory system?

  Internal transport of oxygen and nutrients
• What are the main functions of the circulatory system?

  Transportation, protection, fluid balance, thermoregulation
• What type of circulatory system do insects have?

  Open circulatory system
• How does an open circulatory system function?

  Hemolymph bathes organs directly
• What is a closed circulatory system?

  Blood confined to vessels, separate from interstitial fluid
• What is the cardiovascular system?

  Closed circulatory system in vertebrates
• What is the circulatory fluid in closed systems?

  Blood
• What is the circulatory fluid in open systems?

  Hemolymph
• What is interstitial fluid?

  Fluid between body cells
• What is the heart's primary role?

  Drives circulation
• What is the endocardium?

  Inner lining of the heart and valves
• What is the myocardium?

  Muscular middle layer responsible for pumping
• What is the epicardium?

  Outer covering of the heart
• What is the pericardium?

  Protective fibrous sac around the heart
• What does the right atrium do?

  Receives deoxygenated blood from vena cavae
• What is the function of the right ventricle?

  Pumps deoxygenated blood to lungs
• What does the left atrium do?

  Receives oxygenated blood from lungs
• What is the function of the left ventricle?

  Pumps oxygenated blood to the body
• What are the atrioventricular (AV) valves?

  Tricuspid and Mitral/Bicuspid valves
• What is the role of the AV valves?

  Prevent backflow between atria and ventricles
• What are the semilunar valves?

  Pulmonic and Aortic valves
• What is the function of the semilunar valves?

  Prevent backflow into ventricles
• What are chordae tendineae?

  Fibrous cords attaching AV valves to muscles
• What do chordae tendineae prevent?

  Inversion of AV valves
• What do heart sounds "LUBB" and "DUB" indicate?

  Closure of AV and semilunar valves
• What do arteries do?

  Carry blood away from the heart
• What do veins do?

  Carry blood toward the heart
• What are capillaries?

  Sites of exchange between blood and cells
• What are arterioles?

  Small arteries leading into capillaries
• What are venules?

  Small veins that converge into larger veins
• What are capillary beds?

  Networks of capillaries for chemical exchange
• What is systemic circulation?

  Blood flow between heart and body
• What is pulmonary circulation?

  Blood flow between heart and lungs
• What is coronary circulation?

  Blood supply to the heart muscle itself
• What is single circulation?

  Blood passes through heart once in each circuit
• What is double circulation?

  Oxygenated and deoxygenated blood pumped separately
• What is the pulmocutaneous circuit?

  Blood flows to both lungs and skin
• What is an adaptation of amphibians in terms of heart structure?

  Three-chambered heart (2 atria, 1 ventricle)
• What is a characteristic of reptile hearts?

  Three-chambered heart; some with septum
• What is unique about crocodilian hearts?

  Nearly four-chambered heart