Exam 2 bio 2

Atmospheric pressure at sea level is equal to a column of 760 mm Hg. Oxygen makes up 21 percent of the atmospheric pressure by volume. The partial pressure of oxygen in such conditions is

160 mm Hg

A patient with a blood pressure of 120/75, a pulse rate of 70 beats/minute will have a cardiac output of

4,900mL/minute

When the air in a testing chamber is specially mixed so that its oxygen content is 10% and its overall air pressure is 400 mm Hg, then PO2 is

40 mm Hg

A stroke volume of 70mL/cycle in a heart with a pulse of 72 cycles/minute would result in a cardiac output of about __________

5 L per minute

A person with a tidal volume of 450 mL, a vital capacity of 4,000 mL, and a residual volume of 1,000 mL would have a potential total lung capacity of

5,000 mL

At the summit of a high mountain, the atmospheric pressure is 380 mm Hg. If the atmosphere is still composed of 21 percent oxygen, then the partial pressure of oxygen at this altitude is about

80 mm Hg

A species that has a normal resting systolic blood pressure of greater than 260mm Hg is likely to be

An animal that has a very long distance between its heart and its brain

Lymph hearts are pumping structures that drive lymph through the lymphatic system, returning it to the circulatory system at the large veins entering the heart. Researchers examined rate and strength of pumping of lymph hearts in two species of amphibians, a toad (Bufo marinus) and a frog (Rana catesbiana). During hemorrhage or dehydration, the volume of blood in the circulatory system falls. (E. A. DeGrauw and S. S. Hillman. 2004. General function and endocrine control of the posterior lymph hearts in Bufo marinus and Rana catesbiana. Physiological and Biochemical Zoology 77(4):594-600.) Refer to the paragraph on lymph hearts. What effect would increasing lymph heart pressure have first?

Blood volume would increase

Which of the following mechanisms are used to regulate blood pressure in the closed circulatory system of vertebrates?

Changing the force of heart contraction, constricting and relaxing sphincters on the walls of arterioles, adjusting the volume of blood contained in the veins

How has the avian lung adapted to the metabolic demands of flight?

Gas exchange occurs during both inhalation and exhalation.

You cut your finger, and after putting pressure on the wound for several minutes, you notice that it is still bleeding profusely. What may be the problem?

Platelets are not functioning properly, or there are too few to be effective.

Carbonic anhydride inhibitors cause less movement of carbonic acid toward coat on dioxide production and are used as a prophylactic treatment of altitude sickness. Altitude sickness occurs when a hiker ascends to altitudes where the density of oxygen is low. How does this decrease the symptoms of high altitude sickness?

The excess bicarbonate ions are excreted in the urine and the resulting increase in blood acidity leads to an increase in ventilation

Which of the following statements comparing respiration in fish and mammals is correct?

The movement of the respiratory medium in mammals is bidirectional, but in fish it is unidirectional.

A rabbit taken from a meadow near sea level and moved to a meadow high on a mountainside would have some trouble breathing. Why?

The partial pressure of oxygen in the air at high elevations is lower than at sea level.

Blood is pumped at high pressures in arteries from the heart to ensure that all parts of the body receive adequate blood flow. Capillary beds, however, would hemorrhage under direct arterial pressures. How does the design of the circulatory network contribute to reducing blood pressure to avoid this scenario?

The total cross-sectional diameter of the arterial circulation increases with progression from artery to arteriole to capillary, leading to a reduced blood pressure.

Flying insects typically

Utilize high numbers of mitochondria in flight muscles

The sun shining on a tidal pool during a hot day heats the water. As some water evaporates, the pool becomes saltier, causing

a decrease in its oxygen content.

You are a physician, and you are seeing a patient who complains of abnormal fatigue during exercise. You find that the immediate problem is a buildup of carbon dioxide in the tissues. What is the most likely cause?

abnormal carbonic anhydrase

A normal event in the process of blood clotting is the

activation of prothrombin to thrombin

An anthropologist discovers the fossilized heart of an extinct animal. The evidence indicates that the organism's heart was large, was well-formed, and had four chambers, with no connection between the right and left sides. A reasonable conclusion supported by these observations is that the _____.

animal was endothermic and had a high metabolic rate

Cyanide poisons mitochondria by blocking the final step in the electron transport chain. Human red blood cells placed in an isotonic solution containing cyanide are likely to

be unaffected

An oil-water mixture works as an insecticidal spray against mosquitoes and other insects because it

blocks the openings into the tracheal system

The diagnosis of hypertension in adults is based on the _____

blood pressure being greater than 140 mm Hg systolic and/or greater than 90 mm Hg diastolic

Which of the following conditions would most likely be due to high blood pressure in a mammal?

bursting of blood vessels in capillary beds

During most daily activities, the human respiration rate is most closely linked to the blood levels of

carbon dioxide

Organisms with a circulating body fluid that is distinct from the fluid that directly surrounds the body's cells are likely to have

closed circulatory system

Most of the carbon dioxide produced by humans is

converted to bicarbonate ions by an enzyme in red blood cells

Large proteins such as albumin remain in capillaries rather than diffusing out, resulting in the

development of an osmotic pressure difference across capillary walls

Countercurrent exchange in the fish gills helps to maximize ____

diffusion

atria contract

during systole

The production of red blood cells is stimulated by

erythropoietin

The hormone that stimulates the production of red blood cells, and the organ where this hormone is synthesized, are

erythropoietin and kidney, respectively.

The only vertebrates in which blood flows directly from respiratory organs to body tissues without first returning to the heart are the _____.

fishes

To become bound to hemoglobin for transport in a mammal, atmospheric molecules of oxygen must cross

five membranes-in and out of the cell lining the lung, in and out of the endothelial cell lining an alveolar capillary, and into the red blood cell-to bind with hemoglobin

If, during protein starvation, the osmotic pressure on the venous side of capillary beds drops below the hydrostatic pressure, then

fluids will tend to accumulate in tissues.

To adjust blood pressure independently in the capillaries of the gas-exchange surface and in the capillaries of the general body circulation, an organism would need a(n)

four-chambered heart

In which of the following organisms does blood flow from the pulmocutaneous circulation to the heart before circulating through the rest of the body?

frogs

Among the following choices, which organism likely has the highest systolic pressure?

giraffe

Under identical atmospheric conditions, freshwater _____.

has more oxygen than seawater

A decrease from pH 7.4 to pH 7.2 causes hemoglobin to _____.

increase its binding of H+

Small swollen areas in the neck, groin, and axillary region are associated with

increased activity of the immune system

Some human infants, especially those born prematurely, suffer serious respiratory failure because of

lung collapse due to inadequate production of surfactant

In an open circulatory system, blood is _____.

not always confined to blood vessels and is under lower pressure than in closed circulatory systems

The Bohr shift on the oxygen-hemoglobin dissociation curve is produced by changes in

pH

If a molecule of CO2 released into the blood in your left toe is exhaled from your nose, it must pass through all of the following except

pulmonary vein

What would be the consequences if we were to reverse the direction of water flow over the gills of a fish, moving water inward past the operculum, past the gills, then out the mouth. This reversal of water flow would

reduce efficiency of gas exchange

Which of the following develops the greatest pressure on the blood in the mammalian aorta?

systole of the left ventricle

What will be the long-term effect of blocking the lymphatic vessels associated with a capillary bed?

the accumulation of more fluid in the interstitial areas

Carbon dioxide levels in the blood and cerebrospinal fluid affect pH. This enables the organism to sense a disturbance in gas levels as

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

The greatest difference in the concentration of respiratory gases is found in which of the following pairs of mammalian blood vessels?

the pulmonary vein and the jugular vein

Circulatory systems compensate for _____.

the slow rate at which diffusion occurs over large distances

The velocity of blood flow is the lowest in capillaries because

the total cross-sectional area of the capillaries is greater than the total cross-sectional area of the arteries or any other part of the circulatory system

A human red blood cell in an artery of the left arm is on its way to deliver oxygen to a cell in the thumb. To travel from the artery to the thumb and then back to the left ventricle, this red blood cell must pass through _____.

two capillary beds

Which of the following is the correct sequence of blood flow in birds and mammals?

vena cava → right atrium → right ventricle → pulmonary artery

Which of the following events would be predicted by the bohr shift effect as the amount of carbon dioxide released from your tissues into the blood capillaries increases? The amount of oxygen in

venous blood would decrease

Countercurrent exchange is evident in the flow of _____

water across the gills of a fish and the blood within those gills

Damage to the sinoatrial node in humans

would disrupt the rate and timing of cardiac muscle contractions