biology lecture SI study guide CH 42

Which respiratory organ is most often found only in fully aquatic animals? a. Gills b. Alveoli c. Lungs d. Tracheae e. Skin surface

a. Gills

All known birds and mammals have __________. a. a double circulatory system and a four-chambered heart b. a single circulatory system and a two-chambered heart c. a double circulatory system and a three-chambered heart d. a double circulatory system and a two-chambered heart e. a single circulatory system and a four-chambered heart

a. a double circulatory system and a four-chambered heart

Countercurrent flow in the gills of a fish __________. a. maintains a gradient that enhances diffusion b. interferes with the efficient absorption of oxygen c. speeds up the flow of water through the gills d. means that blood and water flow in the same direction e. enables blood oxygenation in fish regardless of the direction of water flow relative to blood flow

a. maintains a gradient that enhances diffusion

The SA node generates an electrical impulse from its location in __________. a. the right atrium, causing atrial contraction b. the left ventricle wall, from which the impulse is carried to the bundle branches and on to the Purkinje fibers c. the left atrium, causing ventricular contraction d. the left ventricle, causing atrial contraction e. none of the listed locations

a. the right atrium, causing atrial contraction

When you hold your breath, which of the following blood gas changes leads initially to the urge to breathe again? a. Falling oxygen concentration b. Rising carbon dioxide concentration c. Falling carbon dioxide concentration d. Rising oxygen concentration e. None of the listed responses is correct

b. Rising carbon dioxide concentration

An open circulatory system __________. a. has no valves b. allows interstitial fluid to mix freely with vascular fluid c. unlike a closed circulatory system, does not rely on muscle contraction d. is less common in crabs and beetles than in mice and snakes e. restricts the backflow of blood by valves in the trachea

b. allows interstitial fluid to mix freely with vascular fluid

In the alveoli and lung capillaries, carbon dioxide and oxygen are exchanged by means of __________. a. endocytosis b. diffusion c. pinocytosis d. active transport e. osmosis

b. diffusion

Heart valves function to __________ a. mix blood thoroughly as it passes through the heart b. keep blood moving forward through the heart c. slow blood down as it passes through the heart d. control the amount of blood pumped by the heart e. propel blood as it passes through the heart

b. keep blood moving forward through the heart

Blood leaves the inferior vena cava and flows directly into the __________. a. left atrium b. right atrium c. Lungs d. pulmonary artery e. superior vena cava

b. right atrium

Pressure is greatest in the ventricles when __________. a. the atria contract during early systole b. the ventricles contract c. blood arrives at the left atrium d. blood arrives at the right ventricle e. AV valves are open and semilunar valves are closed

b. the ventricles contract

What is the physiological cause of a heart attack? a. Severe angina b. A blood clot moving through the chambers of the heart c. A blood clot lodging in a blood vessel supplying the heart d. Scar tissue in the heart muscle e. Rupture of coronary arteries

c. A blood clot lodging in a blood vessel supplying the heart

In which animal does the circulatory system include a heart and a system of closed vessels? a. Crayfish b. Sea anemone c. Fish d. Beetle e. Sponge

c. Fish

What is atherosclerosis? a. Chest pain due to a partial blockage of the coronary arteries b. Lack of oxygen to the brain, leading to a death of nervous tissue there c. Hardening of the arteries by accumulation of fatty deposits d. A failure of blood to clot e. Damage to or death of cardiac muscle tissue due to a blockage in the coronary arteries

c. Hardening of the arteries by accumulation of fatty deposits

What is unique about blood in pulmonary arteries compared with blood in other arteries? a. It is moving toward the heart. b. Blood in pulmonary arteries is always blue; it is red in all other arteries. c. It is loaded with carbon dioxide. d. It is moving away from the heart. e. There is no difference; it is the same as blood in other arteries

c. It is loaded with carbon dioxide.

Your blood pressure is 120/70. The "120" indicates __________, and the "70" indicates __________. a. arterial pressure; venous pressure b. pressure in the systemic system; pressure in the pulmonary system c. arterial pressure during heart contraction; arterial pressure during heart relaxation d. pressure in the left ventricle; pressure in the right ventricle e. pressure in the left ventricle; pressure in the left atrium

c. arterial pressure during heart contraction; arterial pressure during heart relaxation

The function of the pulmonary circuit in a dog is to __________. a. carry blood through the heart, lungs, and all of the body tissues b. carry absorbed nutrients from the small intestine to the liver c. carry carbon dioxide to the lungs and pick up oxygen from the lungs d. carry oxygen and nutrients to tissues where they are needed e. retrieve waste products from the body tissues

c. carry carbon dioxide to the lungs and pick up oxygen from the lungs

In a fish, blood circulates through __________, whereas in a mammal, it circulates through __________. a. four circuits; two circuits b. two circuits; four circuits c. one circuit; two circuits d. one circuit; four circuits e. two circuits; one circuit

c. one circuit; two circuits

What happens when the CO2 level from cellular respiration increases in the blood? a. The O2 level automatically increases. b. The pH of the cerebrospinal fluid also increases and is detected by O2 sensors in arteries near the heart. c. The medulla, moderated by the pons, signals the heart muscle to beat harder, bringing in more O2. d. A decrease in the pH of the cerebrospinal fluid triggers the brain's breathing control centers, which stimulate diaphragm and rib muscle contractions. e. Cellular respiration decreases.

d. A decrease in the pH of the cerebrospinal fluid triggers the brain's breathing control centers, which stimulate diaphragm and rib muscle contractions

A recording of the electrical activity of a patient's heart shows that the atria are contracting regularly and normally, but every few beats the ventricles fail to contract. Which of the following is probably functioning improperly? a. Aortic semilunar valve b. SA node c. AV valve d. AV node e. Coronary artery

d. AV node

Which of the following is a function of the circulatory system? a. Producing mucus b. Eliminating hormones c. Producing wastes d. Transporting nutrients e. All of the listed responses are correct

d. Transporting nutrients

An individual suffering from __________ has irregularly shaped erythrocytes and may suffer from severe pain and organ swelling. a. atherosclerosis b. stroke c. anemia d. sickle-cell disease

d. sickle-cell disease

Gas exchange in the gills of a bony fish is maximized by which of the following? a. A tracheal system b. Negative pressure breathing c. Alveoli d. Positive pressure breathing e. Countercurrent exchange

e. Countercurrent exchange

Which of the following is a function of erythrocytes (red blood cells)? a. Engulfing bacteria b. Scavenging dead cells c. Synthesizing antibodies d. Engulfing viruses e. None of the listed responses is correct.

e. None of the listed responses is correct.

When we compare the structures and functions of arteries and veins, we find that the walls of arteries are __________, the blood pressure inside arteries is __________, and the blood in arteries is moving __________ the heart. a. thinner; higher; away from b. thicker; lower; toward c. thinner; lower; away from d. thinner; lower; toward e. thicker; higher; away from

e. thicker; higher; away from