Exam 2

In those parts of equatorial Africa where the malaria parasite is most common, the sickle-cell allele constitutes 20% of the β hemoglobin alleles in the human gene pool. With respect to the sickle-cell allele, what should be true of the β hemoglobin locus in U.S. populations of African Americans whose ancestors were from equatorial Africa? (1) The average heterozygosity at this locus should be decreasing over time. (2) There is an increasing heterozygote advantage at this locus. (3) Diploidy is helping to preserve the sickle-cell allele at this locus.(4) Frequency-dependent selection is helping to preserve the sickle-cell allele at this locus.

1 and 3

Xenon gas was measured to have a volume of 15.5 kL. If the volume changes to 0.6 kL and the pressure becomes 44 Pa, what was the original pressure?

1.70 Pa

Atmospheric pressure at sea level is equal to 760, oxygen makes up 21% of volume. PP of oxygen is

160

What is the maximum number of molecules of oxygen that bar-headed goose hemoglobin can bind to?

4

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 the partial pressure of oxygen is

40 mm Hg.

A patient with a BP of 120/75, a pulse rate of 70 beats/minute, a stroke volume of 70 m:/beat, and a respiratory rate of 25 breaths/minute will have a cardiac output of ____________

4900 mL/minute

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 gas is an environment that has a volume of 16.8 L and a pressure of 3.2 atm. If the volume changes to 10.6 L, what will be the new pressure?

5.07 atm

What is the approximate partial pressure of oxygen on top of Mount Everest?

53 mm Hg

What is the approximate oxygen saturation percentage of bar-headed goose hemoglobin on top of Mount Everest?

90%

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

A closed circulatory system

According to Fick's law, which event would cause a decrease in the rate of diffusion?

A decrease in the size of the respiratory membrane (A).

A normal event in the process of blood clotting is the

Activation of prothrombin to thrombin

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

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

_____ in carbon dioxide in your red blood cells, which causes _____ in pH, causes your breathing to speed up.

An increase ... a drop

An anthropologist discovers the fossilized heart of an extinct animal. The evidence indicates the heart was large, was well-formed, and had four chambers, with no connections 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

Which of the following statements is true?

Arthropods have an open circulatory system, while annelids have a closed circulatory system.

What statement about the data in the graph is true?

Bar-headed geese hemoglobin can bind more oxygen at higher altitudes than human hemoglobin.

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

Blocks the opening into the tracheal system

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

Bursting of blood vessels in capillary beds

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

What is one advantage of closed circulatory systems as compared to open circulatory systems?

Closed systems have a higher capacity to direct blood to specific tissues.

Countercurrent exchange in the fish gills helps to maximize

Diffusion

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

How does the dissociation curve for fetal hemoglobin compare to that for maternal hemoglobin?

Fetal hemoglobin has a higher affinity for oxygen than maternal hemoglobin at any partial pressure of oxygen.

Which hypothesis best explains this difference?

Fetal hemoglobin's higher affinity for oxygen helps promote the movement of oxygen from mother to fetus.

In order to fly over Mount Everest, bar-headed geese must fly higher and increase their altitude. What will happen in bar-headed geese as they increase their altitude?

Fewer oxygen molecules will bind to hemoglobin.

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

Fishes

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 hthe highest systolic pressure?

Giraffe

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

Increased activity of the immune system

Which statement about the disease hemophilia is true?

It is caused by the absence of a specific protein crucial for blood clot formation.

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

Lung collaspe due to inadequate production of surfactant

In an open circulatory system, blood pressure is _______________

Not always confined to blood vessels and is under low pressure than in closed circulatory systems

What happens to nutrient macromolecules in an animal's digestive tract?

Nutrient macromolecules are digested into monomers before absorption.

For a gas, which pair of variables are inversely proportional to each other (if all other conditions remain constant)?

P, V

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

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

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

The circulatory system of bony fishes, rays, and sharks are most similar to _____________

The portal system of mammals, where two capillary beds occur sequentially, without passage of blood through pumping chambers

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

The pulmonary vein

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 the 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 o its way to deliver oxygen to a cell in the thumb. To travel the artery to the thumb then back to the left ventricle, this red blood cell must pass through ______

Two capillary beds

Flying insects typically

Utilize high numbers of mitochondria in flight muscles

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

Vena cava --> right atrium --> right ventricle --> pulmonary artery

Countercurrent exchange is evident in the flow of

Water across the gills of fish and the blood within those gills

Damage to the sinoatrial node in humans __________

Would disrupt the rate and timing of cardiac muscle contractions

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.

Which of the following animals would most likely be able to exchange gases effectively when placed in a dry desert environment?

a dolphin

By picking up hydrogen ions, hemoglobin prevents the blood from becoming too _____.

acidic

What is the digestive system microbiome?

all of the bacteria living in a person's digestive system that includes good and bad bacteria

Arteries are distinguished from veins based on all of the following features except the

amount of oxygen present in the blood. Are: direction of blood flow relative to the heart. structure of their walls. blood pressure pushing against the walls of the vessels.

An increase from pH 7.1 to pH 7.5 around hemoglobin causes

an increase in the affinity of hemoglobin to bind oxygen molecules.

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.

Arthropods invaded land about 100 million years before vertebrates did so. This most clearly implies that

arthropods have had more time to coevolve with land plants than vertebrates have had.

Most carbon dioxide is carried from the body tissues to the lungs _____.

as bicarbonate ions (HCO3 -)

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

Most animals are

bulk feeders.

To maintain adequate nutrition, animals require dietary access to certain amino acids. An amino acid that is referred to as "nonessential" would be best described as one that

can be made by the animal's body from other substances.

Reabsorption of water is a major function of the

colon.

In the blood most of the oxygen that will be used in cellular respiration is carried from the lungs to the body tissues _____.

combined with hemoglobin

Most of the carbon dioxide produced by humans is

converted to bicarbonate ions by an enzyme in red blood cells.

People with sickle-cell disease have

defective hemoglobin.

As an example of the relationship between structure and function, the forward-facing eyes shared by all primates help them in

depth perception as they navigate through forests.

Countercurrent exchange in the fish gill helps to maximize

diffusion.

Atria contract __________

during systole

The organization of blood and water flow in a fish's gills increases the fish's ability to

extract oxygen from the water.

The richest source of stored chemical energy in the body is

fat in adipose tissue.

Atherosclerosis is hardening of the arteries caused by

fatty deposits.

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

fishes.

Hydrogen ions produced within human red blood cells are prevented from significantly lowering plasma pH because they bind to

hemoglobin

Hydrogen ions produced within human red blood cells are prevented from significantly lowering plasma pH because they bind to

hemoglobin.

Organisms at which of the following trophic levels increased the most because of the movement of animals onto land?

herbivores and carnivores

The amount of oxygen bound to hemoglobin _____.

increases in the presence of high concentrations of oxygen

One advantage of gas exchange in water is that

it is easy to keep the exchange surface wet.

Bone marrow stem cells are sometimes used to treat certain blood cell diseases, such as

leukemia.

The essential amino acids

must be obtained from the food we eat.

An "internal reservoir" of oxygen in rested muscle is found in oxygen molecules bound to

myoglobin.

The thermoneutral zone of a homeotherm is a

narrow range of external temperatures with a constant metabolic rate.

Sponges, cnidarians, and flatworms lack a specialized gas-exchange surface because

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

Which of the following correctly lists the order of the parts of the human digestive system, from first to last contact with food matter?

oral cavity, pharynx, esophagus, stomach, small intestine, large intestine

Which animal is an ape?

orangutan

An organ system consists of

organs that collectively perform a vital body function.

What happens to pH and breathing rate during exercise?

pH decreases, which causes breathing rate to increase.

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

pH.

Smooth muscle propels food through the alimentary canal by a process called

peristalsis.

You cut your finger, after putting pressure on it for several minutes and it is still bleeding profusely then

platelets are not functioning properly or there are too few to be effective

Organisms that depend largely on external sources of heat to maintain body temperature are called

poikilotherms.

The main function of the hindgut in the grasshopper is to

reabsorb water and compact wastes.

When you hold your breath, which of the following blood gas changes leads initially to the urge to breathe again?

rising carbon dioxide concentration

Jaws appear to have evolved from

skeletal rods that supported gill slits near the mouth.

The vertebrate group that describes all jawed vertebrates with two pairs of limbs is the

tetrapods.

The set of blood vessels with the lowest blood pressure driving flow is

the veins.

Which of the following is likely to have the lowest concentration of O2?

warm saltwater

Gas exchange is more difficult for aquatic animals with gills than for terrestrial animals with lungs because

water contains much less O2 than air per unit volume.