23
Define a closed circulatory system and compare the differences in heart structure for animals with closed circulatory systems.
  1. A closed circulatory system is a system in which the blood mixes with the interstitial fluid. Fish have a two-chambered heart. Amphibians and reptiles have a three-chambered heart, but the latter has little mixing of blood. Mammals and birds have a four-chambered heart and double circulation.
  2. A closed circulatory system is a system in which blood is separate from the interstitial fluid. Fish have a two-chambered heart. Amphibians and reptiles have a three-chambered heart, but the latter has little mixing of blood. Mammals and birds have a four-chambered heart and double circulation.
  3. A closed circulatory system is a system in which blood is separate from the interstitial fluid. Amphibians have a two-chambered heart. Fishes and reptiles have a three-chambered heart, but the latter has little mixing of blood. Mammals and birds have a four-chambered heart and double circulation.
  4. A closed circulatory system is a system in which blood mixes with the interstitial fluid. Amphibians have a two-chambered heart. Fishes and reptiles have a three-chambered heart, but the latter has little mixing of blood. Mammals and birds have a four-chambered heart and double circulation.
24
A circulatory system is the main method for transporting gases and nutrients throughout the body. Explain what happens in a closed circulatory system and compare a closed circulatory system to an open closed circulatory system.
  1. Blood in closed circulatory system is present inside blood vessels and circulates unidirectional from the heart, around the systemic circulatory route, then returns to the heart. It is less controlled and structured than an open circulatory system, but nutrients and waste products are transported more efficiently.
  2. Blood in closed circulatory system is not enclosed in blood vessels, but is pumped into a hemocoel, which circulates around the organs, then reenters the heart through ostia. It is more structured, controlled, and nutrients and waste products are transported more efficiently.
  3. Blood in closed circulatory system is not enclosed in blood vessels, but is pumped into a hemocoel, which circulates around the organs, then reenters the heart through ostia. It is less controlled and structured than an open circulatory system, but nutrients and waste products are transported more efficiently.
  4. Blood in a closed circulatory system is present inside blood vessels, circulates unidirectional from heart around the systemic circulatory route, and then returns to the heart. It is more structured, controlled, and nutrients and waste products are transported more efficiently than in open circulatory system.
25
What is one advantage of a four chambered heart over a three chambered heart?
  1. Oxygenated blood carried by the right side of the heart is completely separated from the left side carrying deoxygenated blood, which assists in more efficient movement of oxygen around the body and aids in allowing the body to quickly move when needed.
  2. A four-chambered heart keeps oxygenated and deoxygenated blood separated and has double circulation whereas a three-chambered heart has a single circulation. This assists in more efficient movement of oxygen around the body.
  3. Oxygenated and deoxygenated blood are kept separate in a four-chambered heart, which assists in more efficient movement of carbon dioxide around the body.
  4. Oxygenated and deoxygenated blood are kept separate in a four-chambered heart, which assists in more efficient movement of oxygen around the body and aids in allowing the body to move quickly when needed.
26
What are red blood cells also known as?
  1. lymphocytes
  2. monocytes
  3. erythrocytes
  4. basophils
27
How does the structure of red blood cells allow them to deliver oxygen to the cells of the body?
  1. Their size and shape allow them to carry and transfer oxygen.
  2. Their disc shape contains many small vesicles that allow them to carry and transfer oxygen.
  3. They have nuclei and do not contain hemoglobin.
  4. They contain coagulation factors and antibodies.
28
Which of the following best describes plasma?
  1. It is a protein synthesized in the liver.
  2. It is a liquid that contains only lipids and antibodies.
  3. It is a blood component that is separated by spinning blood.
  4. It is an antibody produced in the mucosal lining.
29
What is the heart’s internal pacemaker?
  1. An internal implant sends an electrical impulse through the heart.
  2. It is an electrical impulse that starts in cardiac muscle cells at the sinoatrial node.
  3. It is the excitation of cardiac muscle cells at the atrioventricular node followed by the sinoatrial node.
  4. It starts in the aorta.
30
Cardiomyocytes are similar to skeletal muscle because _______.
  1. they beat involuntarily
  2. they are attached to bones
  3. they pulse rhythmically
  4. they are striated
31

Illustration of human heart with features of internal anatomy labeled counterclockwise starting from the top left: pulmonary artery, superior vena cava, right atrium, pulmonary valve (semilunar), tricuspid valve (atrioventricular), right ventricle, inferior vena cava, aorta, pulmonary artery, left atrium, aortic valve (semilunar), mitral valve (atrioventricular), left ventricle

The diagram shows the internal anatomy of the heart. How would blood circulation beyond the heart be affected if the pulmonary valve could not open?

  1. Blood could not reach the rest of the body.
  2. Blood could not reach the lungs.
  3. Blood could not return from the lungs.
  4. Blood could not return from the rest of the body.
32

Illustration of human heart with features of internal anatomy labeled counterclockwise starting from the top left: pulmonary artery, superior vena cava, right atrium, pulmonary valve (semilunar), tricuspid valve (atrioventricular), right ventricle, inferior vena cava, aorta, pulmonary artery, left atrium, aortic valve (semilunar), mitral valve (atrioventricular), left ventricle

The diagram below shows the internal anatomy of the heart. How would blood circulation beyond the heart be affected if the tricuspid valve could not open?

  1. Blood could not enter the pulmonary veins; therefore, it could not reach the lungs.
  2. Blood could not enter the pulmonary artery; therefore, it could not reach the heart.
  3. Blood could not enter the pulmonary artery; therefore, it could not reach the lungs.
  4. Blood could not enter the pulmonary veins; therefore, it could not reach the heart.
33
Why is it useful for blood to travel slowly through capillary beds?
  1. To allow antibodies to enter infected cells and to promote the diffusion of fluid into the interstitial space.
  2. To assist with gas and nutrient exchange and to prevent the diffusion of fluid into the interstitial space.
  3. To assist with gas and nutrient exchange and to promote the diffusion of fluid into the interstitial space.
  4. To allow antibodies to enter infected cells and to prevent the diffusion of fluid into the interstitial space.