Chapter 42: Circulation and Gas Exchange

If resistance increases in the capillary beds of the lung, which structure would be affected first?

• Right ventricle

• Aorta

• Right atrium

• Left atrium

• Left ventricle

Which chambers of the heart respectively receive and pump oxygen-poor blood?

• right atrium and right ventricle

• Left atrium and left ventricle

• Right atrium and left ventricle

• Left atrium and right ventricle

Which of the following correctly lists the sequence of blood flow in mammals?

• Venae cavae, right atrium, right ventricle, pulmonary arteries, lungs, pulmonary veins, left atrium, left ventricle, aorta

• Aorta, left ventricle, left atrium, pulmonary veins, lungs, pulmonary arteries, right ventricle, right atrium, venae cavae

• Lungs, pulmonary arteries, right ventricle, right atrium, venae cavae, pulmonary veins, left atrium, left ventricle, aorta

• Aorta, left ventricle, left atrium, pulmonary veins, lungs, pulmonary arteries, right atrium, right ventricle, venae cavae

Which of the following factors would increase the release of oxygen from hemoglobin?

• Increased exercise and decreased blood pH

• Increased blood pH and increased blood P_O2

• Decreased exercise and increased blood pH

• Decreased blood P_O2 and decreased exercise

• Decreased blood P_O2 and increased blood pH

To control breathing, the medulla of the human brain monitors the ________ of the blood and then sends out signals so that appropriate physiological adjustments can be made.

• pH

• carbon dioxide level

• oxygen level

• hemoglobin level

• erythrocyte count

An open circulatory system __________.

• • allows interstitial fluid to mix freely with vascular fluid

• is less common in crabs and beetles than in mice and snakes

• unlike a closed circulatory system, does not rely on muscle contraction

• restricts the backflow of blood by valves in the trachea

• has no valves

What is unique about blood in pulmonary arteries compared with blood in other arteries?

• It is loaded with carbon dioxide

• Blood in pulmonary arteries is always blue; it is red in all other arteries

• It is moving away from the heart

• There is no difference; it is the same as blood in other arteries

• It is moving toward the heart

Heart valves function to __________.

• keep blood moving in the correct direction

• mix blood thoroughly as it passes through the heart

• control the amount of blood pumped by the heart

• slow down blood as it passes through the heart

• propel blood as it passes through the heart

Which of the following is an example of a portal vein?

• A blood vessel carrying blood from the stomach to the liver

• A blood vessel carrying blood from the heart to the lungs

• 
  A blood vessel carrying blood from the lungs to the heart

• A blood vessel carrying blood from the major muscles of the lower leg back to the heart

• A blood vessel carrying blood from the heart to the muscles of the lower leg

What is the physiological cause of a heart attack?

• A blood clot lodging in a blood vessel supplying the heart

• Rupture of coronary arteries

• Severe angina

• A blood clot moving through the chambers of the heart

• Scar tissue in the heart muscle