Chapter 34

True or false? The circulatory systems of land-dwelling vertebrates are composed of two pumping circuits: the systemic circulation, which is a lower-pressure circuit to the lung, and the pulmonary circulation, which is a higher-pressure circuit to the rest of the body. True False

False

Which statement regarding the mammalian heart is correct? Oxygen-loaded blood moves only through the right side of the heart. Blood is pumped from the heart via the atria. In the adult heart, blood in the right chambers of the heart cannot enter the left chambers without passing through the lungs. Blood arrives at the heart via the ventricles. When the right atrium contracts, it forces blood into the left atrium.

In the adult heart, blood in the right chambers of the heart cannot enter the left chambers without passing through the lungs.

An adaptive advantage of having a 4 chambered heart, as found in mammals, over the 2 chambered heart in fish is that the additional chambers in the mammalian heart reduces blood flow to the respiratory organ full oxygenated blood returning to the fish heart can undergo additonal pumping to reach higher pressures increased energy demands of endotherms requires that their circulatory systems deliver ~ 10x as much fuel and oxygen to their tissues as ectotherms, which is possible with the mammalian heart ectotherms can tolerate higher environmental pressures

increased energy demands of endotherms requires that their circulatory systems deliver ~ 10x as much fuel and oxygen to their tissues as ectotherms, which is possible with the mammalian heart

The fluid that moves around in the circulatory system of a typical arthropod, such as an insect is the intracellular fluid interstitial fluid blood plasma digestive juices cytosol

interstitial fluid

From the pulmonary veins, blood flows to the _____. right atrium left atrium aorta capillaries of the lungs posterior vena cava

left atrium

From the pulmonary veins, blood flows to the _____. right atrium left atrium aorta capillaries of the lungs posterior vena cava

left atrium

Which chamber pumps oxygenated blood to all parts of the body via the aorta? right ventricle left atrium left ventricle superior vena cava right atrium

left ventricle

Sponges, cnidarians, and flatworms lack a specialized gas exchange surface because countercurrent exchange mechanisms cannot function well in their living conditions. they are too large for a circulatory system to operate well. they live without need for oxygen. they do not produce carbon dioxide. nearly all of their cells are in direct contact with the external environment.

nearly all of their cells are in direct contact with the external environment.

From the capillaries of the abdominal organs and hind limbs, blood flows to the _____. right atrium left atrium aorta capillaries of the lungs posterior vena cava

posterior vena cava

Blood pressure is highest in the _____. aorta inferior vena cava superior vena cava pulmonary artery capillaries

aorta

Most carbon dioxide is carried from the body tissues to the lungs _____. as bicarbonate ions (HCO3 -) combined with hemoglobin by the trachea as hydrogen ions (H+) dissolved in blood plasma

as bicarbonate ions (HCO3 -)

Arteries carry blood _____. away from capillaries away from the heart and away from the lungs to the heart and away from the lungs to the heart only away from the heart only

away from the heart only

The smallest airway through which inspired air passes before gas exchange occurs in the mammalian lungs is the _____. larynx trachea bronchiole bronchus pharynx

bronchiole

The _____ has(have) the thinnest walls. aorta capillaries inferior vena cava pulmonary artery right ventricle

capillaries

Carbon dioxide enters the blood at the _____. capillaries of the lungs capillaries of the abdominal organs capillaries of the hind limbs capillaries of the head and forelimbs capillaries of the head, forelimbs, abdominal organs, and hind limbs

capillaries of the head, forelimbs, abdominal organs, and hind limbs

In the blood most of the oxygen that will be used in cellular respiration is carried from the lungs to the body tissues _____. as bicarbonate ions (HCO3 -) combined with hemoglobin by the trachea water (H2O) dissolved in blood plasma

combined with hemoglobin

Countercurrent exchange in the fish gill helps to maximize blood pressure. diffusion. endocytosis. osmosis. active transport.

diffusion

In which of the following animals are the circulatory fluid and interstitial fluid considered to be the same body fluid? fishes jellyfish and cnidarians grasshoppers dogs sparrows

grasshoppers

Pulse is a direct measure of cardiac output blood pressure breathing rate heart rate stroke volume

heart rate

Deoxygenated blood is pumped by the right ventricle to the lungs via the superior vena cava left atrium left ventricle pulmonary arteries pulmonary veins

pulmonary arteries

Blood returns to the heart via the _____. aorta pulmonary arteries pulmonary veins aorta and pulmonary arteries aorta and pulmonary veins

pulmonary veins

Blood returns to the heart via the _____. aorta pulmonary arteries pulmonary veins aorta and pulmonary arteries aorta and pulmonary veins

pulmonary veins

From the anterior vena cava, blood flows to the _____. right atrium left atrium aorta capillaries of the lungs posterior vena cava

right atrium

When you hold your breath, which of the following blood gas changes first leads to the urge to breathe? rising CO2 rising O2 falling O2 falling CO2 rising CO2 and falling O2

rising CO2

Gas exchange in the aquatic salamander known as the axolotl is correctly described as active transport to move oxygen into the salamander from the water. carrier-mediated transport to move oxygen into the salamander from the water. facilitated diffusion of carbon dioxide from the salamander into the water. active transport of carbon dioxide from the salamander into the water. simple diffusion of oxygen into the salamander from the water.

simple diffusion of oxygen into the salamander from the water.

Which of the following develops the greatest pressure on the blood in the mammalian aorta? systole of the left atrium diastole of the right ventricle systole of the left ventricle diastole of the right atrium diastole of the left atrium

systole of the left ventricle

Countercurrent exchange is evident in the flow of water across the skin of a frog and that of blood within the ventricle of its heart. the flow of air within the primary bronchi of a human and that of blood within the pulmonary veins. the flow of blood in the dorsal vessel of an insect and that of air within its tracheae. the flow of fluid out of the arterial end of a capillary and that of fluid back into the venous end of the same capillary. the flow of water across the gills of a fish and that of blood within those gills.

the flow of water across the gills of a fish and that of blood within those gills.

Carbon dioxide levels in the blood and cerebrospinal fluid affect their pH. This enables the organism to sense a disturbance in gas levels as the brain alters the pH of the cerebrospinal fluid to force the animal to retain more or less carbon dioxide. the medulla oblongata, which is in contact with cerebrospinal fluid, monitors pH and uses this measure to control breathing. the medulla oblongata is able to control the concentration of bicarbonate ions in the blood. stretch receptors in the lungs cause the medulla oblongata to speed up or slow breathing. the brain directly measures and monitors carbon dioxide and causes breathing changes accordingly.

the medulla oblongata, which is in contact with cerebrospinal fluid, monitors pH and uses this measure to control breathing.

Circulatory systems compensate for the need to cushion animals from trauma. temperature differences between the lungs and the active tissue. the slow rate at which diffusion occurs over large distances. the problem of communication systems involving only the nervous system. the need fetal organisms have for maintaining an optimal body temperature.

the slow rate at which diffusion occurs over large distances.

Which of the following have valves within them to prevent backflow? arteries veins capillaries arterioles

veins

_____ in carbon dioxide in your red blood cells, which causes _____ in pH, causes your breathing to speed up. An increase ... a rise A decrease ... a rise An increase ... a drop A decrease ... a drop Actually, it is the rise and fall of oxygen, not carbon dioxide, that controls breathing.

An increase ... a drop

Which of the following best describes an artery? Arteries carry oxygenated blood. Arteries carry blood away from capillaries. Arteries contain valves. Arteries have thin walls compared with veins. Arteries carry blood away from the heart.

Arteries carry blood away from the heart

How are gases transported in insect bodies? In open circulatory systems In closed circulatory systems In tracheal systems

In tracheal systems

What is the function of a circulatory system? It exchanges oxygen and carbon dioxide with the outside air. It acts as a reservoir for the storage of blood. It is the site of blood cell production. It brings a transport liquid into close contact with all cells in the body.

It brings a transport liquid into close contact with all cells in the body.

What is the function of the left ventricle? It pumps deoxygenated blood to the lungs via the pulmonary circulation. It pumps oxygenated blood around the body via the systemic circulation. It receives deoxygenated blood from the lungs. It receives oxygenated blood from the lungs.

It pumps oxygenated blood around the body via the systemic circulation.

Which statement about human blood vessels is correct? Veins transport blood from the heart to the capillaries. Arteries carry blood toward the atria of the heart. The pulmonary artery carries oxygen-rich blood from the lungs. Pulmonary veins carry oxygen-rich blood to the heart. Arteries carry oxygenated blood; veins carry oxygen-poor blood.

Pulmonary veins carry oxygen-rich blood to the heart.

Why do the circulatory systems of land vertebrates have separate circuits to the lungs and to the rest of the body? The large decrease in blood pressure as blood moves through the lungs may prevent efficient circulation through the rest of the body. Land vertebrates are bigger and require more tubing to reach all areas of the body. Blood is pumped to the lungs to be oxygenated before being pumped to the rest of the body. The circuits increase the amount of surface area available for the diffusion of gases and nutrients in the body.

The large decrease in blood pressure as blood moves through the lungs may prevent efficient circulation through the rest of the body.

As in Edgar Allan Poe's short story "The Tell-Tale Heart" a heart can continue to heat after it is removed from the body, because SA node(pacemaker) cells contract without nervous system input impulses from the AV node spread rapidly to walls of atria powerful ventricular contractions induce rebound contractions pulling of blood in the heart maintains the heartbeat

SA node(pacemaker) cells contract without nervous system input

Which event occurs first during diastole? The atria and ventricles contract simultaneously. The atria contract while blood flows into the relaxed ventricles. The atria and ventricles are relaxed, and blood flows into the atria. Blood flows into the relaxed atria while the ventricles contract.

The atria and ventricles are relaxed, and blood flows into the atria.

Which event of the cardiac cycle occurs when systolic blood pressure is measured? The ventricles contract, carrying blood into the aorta, and blood flows into the relaxed atria. The atria and ventricles contract simultaneously. The atria contract while blood flows into the relaxed ventricles. The atria and ventricles are relaxed, and blood flows into the atria.

The ventricles contract, carrying blood into the aorta, and blood flows into the relaxed atria.

Which of the following statements about blood circulation in the body is true? Deoxygenated blood flowing through the pulmonary veins is carried to the right atrium. As the right ventricle contracts, it sends oxygenated blood through the aorta to all tissues of the body. During one cardiac cycle, the two ventricles contract first, and then the two atria contract. Valves prevent the backflow of blood into the atria and ventricles.

Valves prevent the backflow of blood into the atria and ventricles.

Stroke occurs when _____. a blood clot enters and blocks one of the coronary arteries a blood clot dislodges from a vein and moves into the lung, where it blocks a pulmonary artery a blood clot enters the cerebral circulation, blocking an artery and causing the death of brain tissue the walls of an artery in the leg accumulate deposits and lose their flexibility and elasticity the pacemaker of the heart becomes defective, producing an irregular heartbeat

a blood clot enters the cerebral circulation, blocking an artery and causing the death of brain tissue

By picking up hydrogen ions, hemoglobin prevents the blood from becoming too _____. acidic basic thick low in oxygen concentration red

acidic

Air-breathing insects carry out gas exchange across all parts of their thin cuticular exoskeleton. in their specialized external gills. in the alveoli of their lungs. across the finest branches of the trachea and cell membranes. in their specialized internal gills.

across the finest branches of the trachea and cell membranes.