UMKC Bio 109 Ch. 40-43 (Polls, MB, and Problems Sets)

Tunas, sharks, penguins, and dolphins all have a basic fusiform shape, tapered at both ends. What explains this similarity in shape?

A. The similarity is due to convergent evolution because all these animals share similar environmental challenges.

B. The similarity is due to homology, based on shared ancestry.

C. All fast-swimming aquatic vertebrates have this shape.

A. The similarity is due to convergent evolution because all these animals share similar environmental challenges.

Select the correct statement describing feedback control in animals.

A. An animal may be a regulator for one environmental variable but a conformer for another.

B. Ectotherms are regulators with respect to temperature.

C. Positive feedback loops contribute to homeostasis.

A. An animal may be a regulator for one environmental variable but a conformer for another.

How do endotherms and ectotherms differ?

A. Endotherms and ectotherms differ in the means by which they regulate their body temperature.

B. Endotherms are warm-blooded and ectotherms are cold-blooded.

C. Endotherms are regulators and ectotherms are conformers.

A. Endotherms and ectotherms differ in the means by which they regulate their body temperature.

Which statement about endotherms and ectotherms is correct?

A. Ectotherms are more primitive than endotherms.

B. Ectotherms are more abundant and diverse than endotherms.

C. Endothermy is a more successful strategy for thermoregulation than ectothermy.

B. Ectotherms are more abundant and diverse than endotherms.

Look at the graphs and choose the correct statement describing the relationship between BMR (basal metabolic rate) and body mass of mammals. (Look carefully at the quantity being displayed on the y-axis of each figure.)

A. Small mammals have lower BMR, but use more calories per kilogram than large mammals.

B. BMR is roughly proportional to body mass squared.

C. Large mammals have lower basal metabolic rates than small mammals.

A. Small mammals have lower BMR, but use more calories per kilogram than large mammals.

Select the correct statement about essential nutrients.

A. Essential nutrients must be obtained from diet.

B. All animals require an identical set of essential nutrients.

C. Due to their biochemical sophistication, humans have to ingest fewer essential nutrients than do other animals.

A. Essential nutrients must be obtained from diet.

Bacteria in the human gut are which of the following?

A. all pathogens

B. both pathogens and mutualists

C. all mutualists

B. both pathogens and mutualists

Identify the roles played by human gut bacteria.

A. Ulcers are caused by the acid-tolerant bacterium Helicobacter pylori.

B. Human gut bacteria synthesize all essential vitamins required by humans.

C. The human appendix houses mutualistic bacteria that digest cellulose.

A. Ulcers are caused by the acid-tolerant bacterium Helicobacter pylori.

Consider the interior surface of the human stomach and its secretions, shown in the figure. Why doesn't gastric juice, composed of hydrochloric acid and a protease called pepsin, digest the cells that line the stomach?

A. Digestion doesn't begin until the small intestine.

B. Chief cells release pepsin in an inactive form. HCl in the stomach converts pepsin to an active form of the enzyme called pepsinogen by clipping off a small portion of the molecule to expose its active site.

C. The stomach lining secretes mucus, a mixture of glycoproteins, cells, salts, and water.

C. The stomach lining secretes mucus, a mixture of glycoproteins, cells, salts, and water.

Many people have a tendency to gorge on rich, fatty foods. How could such a preference have evolved?

A. In ancestral hunter-gatherer communities, individuals with a tendency to gorge on such foods when available would have had a selective advantage.

B. Fatty foods are very rich in calories and consuming them is an efficient way to gain weight.

C. Most people find fatty foods tasty and satisfying.

A. In ancestral hunter-gatherer communities, individuals with a tendency to gorge on such foods when available would have had a selective advantage.

Which of the following would increase the rate of heat exchange between an animal and its environment?

A. feathers or fur

B. vasoconstriction near the skin

C. blubber or a fat layer under the skin

D. wind blowing across the body surface

E. all of the above

D. wind blowing across the body surface

Homeostatic mechanisms:

A. keep variables exactly at the set point

B. help to keep a relatively constant internal environment in the body

C. act to keep values out of the normal range

D. usually operate by positive feedback

E. produce most disease conditions

B. help to keep a relatively constant internal environment in the body

A(n) _________ is an animal that has a relatively variable body temperature, whereas a(n) _________ is an animal that maintains a relatively stable body temperature

A. endotherm; ectotherm

B. ectotherm; endotherm

C. homeotherm; poikilotherm

D. poikilotherm; homeotherm

E. ectotherm; poikilotherm

D. poikilotherm; homeotherm

How is positive feedback different from negative feedback?

A. positive feedback benefits the organism, but negative feedback is harmful

B. positive feedback's effector responses are in the same direction as the initiating stimulus, whereas negative feedback's effector responses are in the opposite direction

C. in positive feedback, the effector's response increases some parameter (such as body temperature), whereas negative feedback the parameter decreases

D. positive feedback systems have only effectors, whereas negative feedback systems have only receptors

E. positive feedback mechanisms are more frequently encountered in the control of homeostasis than negative feedback mechanisms

B. positive feedback's effector responses are in the same direction as the initiating stimulus, whereas negative feedback's effector responses are in the opposite direction

How are gases transported in insect bodies?

A. In tracheal systems

B. In open circulatory systems

C. In closed circulatory systems

A. In tracheal systems

Which statement about lipoproteins is correct?

A. High-density lipoproteins are a form of cholesterol considered the "good" type to have in blood plasma.

B. High-density lipoproteins are cholesterol transporters in the blood.

C. Low-density lipoproteins are the principal component of atherosclerotic plaques.

B. High-density lipoproteins are cholesterol transporters in the blood.

Why does the velocity of blood slow greatly as blood flows from arterioles into capillaries?

A. Because capillary beds have a total cross-sectional area much greater than the total cross-sectional area of the arterioles.

B. Because the narrow capillaries offer great resistance to blood flow.

C. Because capillary beds are the site of nutrient and oxygen delivery to tissues.

A. Because capillary beds have a total cross-sectional area much greater than the total cross-sectional area of the arterioles.

Select the correct statement about capillary beds.

A. Capillary beds are the site of nutrient and oxygen delivery to tissues.

B. Capillary beds have a total cross-sectional area much smaller than the total cross-sectional area of major arteries.

C. Capillary beds join arteries and veins.

A. Capillary beds are the site of nutrient and oxygen delivery to tissues.

The metabolic rate of a fasting, non-stressed ectotherm at rest at a specific temperature is called:

A. SMR

B. BMR

C. STP

D. ATP

E. ECG

A. SMR

Which of the following would increase the rate of heat exchange between an animal and its environment?

A. feathers or fur

B. vasoconstruction near the skin

C. blubber or a fat layer under the skin

D. wind blowing across the body surface

E. all of the above

D. wind blowing across the body surface

Compared with a smaller cell, a larger cell of the same shape has _____.

A. less surface area.

B. less surface area per unit of volume.

C. a smaller average distance between its mitochondria and the external source.

D. a smaller cytoplasm-to-nucleus ratio.

E. equal surface area per unit of volume.

B. less surface area per unit of volume.

A countercurrent system between substance A and substance B:

maximizes the exchange by having A and B flow in the same direction.

A. minimizes the exchange by having A and B flow in the same direction.

B. maximizes the exchange by having A and B flow in opposite directions.

C. minimizes the exchange by having A and B flow in opposite directions.

B. maximizes the exchange by having A and B flow in opposite directions.

Compare an animal with a gastrovascular cavity to an animal with a tube-type digestive system. What is(are) the major advantage(s) of having a tube?

A. It allows the animal to consume a second meal while the first is being digested.

B. It permits development of specialized enzymes and concentration of digestive juices in different regions.

C. It permits more time for enzymatic action.

Additional physical cutting and grinding of the food bolus is made possible.

D. All of the above are advantages

D. All of the above are advantages

Some nutrients are considered "essential" in the diets of certain animals because:

A. Only those animals use the nutrients.

B. Those nutrients are subunits of important polymers.

C. Those nutrients are necessary coenzymes.

D. Only some foods contain those nutrients.

E. Those nutrients cannot be synthesized by the animal.

E. Those nutrients cannot be synthesized by the animal.

The primary responsibility of this segment of the alimentary canal is the recovery of water that has entered the canal as the solvent of digestive juices.

A. microvilli

B. large intestine

C. stomach

D. cecum

E. pancreas

B. large intestine

What happens in the small intestine?

A. Mostly water is absorbed.

B. There is no digestion, but nutrients are absorbed.

C. Considerable bacterial action occurs on the food.

D. Food is digested and the nutrients are absorbed.

D. Food is digested and the nutrients are absorbed.

This flap of cartilage prevents food from entering the trachea.

A. pharynx

B. epiglottis

C. larynx

D. glottis

E. esophageal sphincter

B. epiglottis

Some nutrients are considered "essential" in the diets of certain animals because

A. only those animals use the nutrients

B. those nutrients are subunits of important polymers

C. those nutrients are necessary coenzymes

D. only some foods contain those nutrients

E. those nutrients cannot be synthesized by the animal

E. those nutrients cannot be synthesized by the animal

Compare an animal with a gastrovascular cavity to an animal with a tube-type digestive system. What is (are) the major advantage(s) of having a tube?

A. it allows the animal to consume a second meal while the first is being digested

B. it permits the development of specialized enzymes and concentration of digestive juices in different regions

C. it permits more time for enzymatic action

D. additional physical cutting and grinding of the food is made possible

E. all of the above are advantages

E. all of the above are advantages

Individuals whose diet consists primarily of corn would most likely become:

A. malnourished

B. obese

C. overnourished

D. anemic

E. undernourished

A. malnourished

How do the digestion and absorption of fat differ from the digestion and absorption of carbohydrates?

A. processing of fats does not require any digestive enzymes; the processing of carbohydrates does

B. fat absorption occurs in the stomach; carbohydrates are absorbed by the small intestine

C. most absorbed fat first enters the lymphatic system; carbohydrates directly enter the blood

D. carbohydrates need to be emulsified before they can be digested; fats do not

E. fat must be worked on by bacteria in the large intestine before it can be absorbed; carbohydrates do not

C. most absorbed fat first enters the lymphatic system; carbohydrates directly enter the blood

Each person makes more than 1 million different B cell antigen receptors and more than 10 million different T cell antigen receptors. How is such diversity in antigen receptors generated?

A. Genes for individual antigen-binding sites have a very high rate of mutation, generating great diversity.

B. By combining variable elements, the immune system assembles many different receptors from a much smaller collection of parts.

C. A large percentage of the vertebrate genome is devoted to genes for individual antigen-binding sites.

B. By combining variable elements, the immune system assembles many different receptors from a much smaller collection of parts.

Because antigen receptor genes are randomly rearranged, some immature lymphocytes produce receptors specific for epitopes on the organism's own molecules. Why doesn't the immune system attack these molecules on the body's cells and tissues?

A. The body's cells are immune to such attack.

B. Only a very few lymphocytes produce receptors that attack the body's own molecules, so it's not a problem.

C. B and T cells with receptors specific for the body's own molecules are destroyed by apoptosis.

C. B and T cells with receptors specific for the body's own molecules are destroyed by apoptosis.

What is the role of recombinase in generating lymphocyte diversity?

A. Recombinase combines DNA from human and viral origin.

B. Early in B cell development, recombinase links one light-chain V gene segment to one J gene segment.

C. Recombinase splices RNA to produce variable transcripts.

B. Early in B cell development, recombinase links one light-chain V gene segment to one J gene segment.

How does an antihistamine reduce allergy symptoms?

A. An antihistamine binds pollen antigens, preventing them from provoking an allergic reaction.

B. An antihistamine kills mast cells, blocking an allergic reaction.

C. An antihistamine blocks receptors for inflammatory chemicals released from granules within mast cells.

C. An antihistamine blocks receptors for inflammatory chemicals released from granules within mast cells.

Select the correct statement about the immune system.

A. Adaptive immunity is characteristic of invertebrates and vertebrates.

B. Antibodies are secreted by T cells.

C. All antigen receptors produced by a single B cell or T cell are identical and bind to the same epitope.

C. All antigen receptors produced by a single B cell or T cell are identical and bind to the same epitope.

All gases exchanged between air and blood in mammals occurs across the walls of the:

A. trachea

B. bronchi

C. alveoli

D. bronchioles

E. epiglottis

C. alveoli

What determines the direction of respiratory gas movement?

A. solubility in water

B. the partial pressure gradient

C. the temperature

D. the molecular weight and size of the gas molecule

E. all of the above

B. the partial pressure gradient

Fluid is forced out of systemic capillaries at the arteriolar end because:

A. The blood pressure is less than that of the interstitial fluid.

B. The osmotic pressure of the interstitial fluid is greater than that of the blood.

C. The osmotic pressure of the interstitial fluid is greater than the blood pressure.

D. The osmotic pressure of the blood is greater than the hydrostatic pressure of the interstitial fluid.

E. The blood pressure is greater than the osmotic pressure of the blood.

E. The blood pressure is greater than the osmotic pressure of the blood.

Which of the following is true about veins?

A. Veins have thicker walls than arteries.

B. Veins carry blood away from the heart.

C. All veins carry deoxygenated blood.

D. Veins have valves that serve to maintain a unidirectional flow of blood.

D. Veins have valves that serve to maintain a unidirectional flow of blood.

During exhalation in humans, air moves from the bronchus into the:

A. bronchioles

B. alveoli

C. nostrils

D. pharynx

E. trachea

E. trachea

For a molecule of CO2 released into the blood in your right toe to eventually travel out of your nose, it must pass through all of the following structures except the:

A. pulmonary vein

B. alveolus

C. trachea

D. right ventricle

E. right atrium

A. pulmonary vein

Circulatory systems compensate for:

A. temperature differences between the lungs and the active tissue.

B. the slow rate at which diffusion occurs over large distances.

C. the need to cushion animals from trauma.

D. all of the above.

B. the slow rate at which diffusion occurs over large distances.

These autorhythmic cells located in the wall of the right atrium control the rate and timing at which all cardiac muscle cells contract.

A. Sinoatrial (SA) node

B. Atroventrical (AV) node

C. Semilunar (SL) node

D. Purkinje fibers

E. Bundle branches

A. Sinoatrial (SA) node

The exchange of gases between interstitial fluid and the blood occurs in:

A. arteries

B. arterioles

C. capillaries

D. veins

E. venules

C. capillaries

Circulatory systems compensate for:

A. temperature differences between the lungs and the active tissue

B. the slow rate at which diffusion occurs over large distances

C. the need to cushion animals from trauma

D. all of the above

B. the slow rate at which diffusion occurs over large distances

Which of the following statements concerning an open circulatory system is true?

A. a heart is not required to pump the circulatory fluid

B. an open circulatory system has higher blood pressure and is less energy efficient than a closed system

C. the circulatory fluid is also the interstitial fluid

D. the circulatory fluid does not require respiratory pigments for O2 transport

E. the lower pressures provide for more effective delivery of O2 than is possible with a closed system

C. the circulatory fluid is also the interstitial fluid

If the atrioventricular node (AV node) were surgically removed from the heart without disrupting signal transmission to the Purkinje fibers, what would happen?

A. no apparent effect on heart activity would be observed

B. only the ventricles would contract

C. the heart rate would decrease

D. only the atria would contract

E. atria and ventricles would contract at approximately the same time

E. atria and ventricles would contract at approximately the same time

Which of the following kills invading microbes?

A. Lysozymes

B. Stomach acid

C. Intestinal enzymes

D. All of the above

E. None of the above

D. All of the above

A body cell that has been infected by a virus (or some other pathogens) will produce interferons to warn nearby cells to prepare for possible infection. Interferons are:

A. Cells in the immune system

B. Pathogens

C. Proteins

D. New DNA

C. Proteins

Your body has millions of different antibodies for detecting millions of different antigens because:

A. you have millions of different antibody genes.

B. antibody genes undergo rearrangement.

C. antibody genes undergo antigen shifting.

D. all of the above.

E. none of the above.

B. antibody genes undergo rearrangement.

Which type of surface marker is normally present on every nucleated cell in your body?

A. B receptor

B. T receptor

C. Class I MHC

D. Class II MHC

E. all of the above

C. Class I MHC

Memory cells:

A. produce allergens.

B. are responsible for passive immunity.

C. prevent an animal from encountering certain antigens.

D. provide an accelerated immune response upon second exposure to a particular antigen.

E. all of the above.

D. provide an accelerated immune response upon second exposure to a particular antigen.

Which of the following would prevent allergic attacks?

A. blocking the attachment of the IgE antibodies to the mast cells

B. blocking the antigenic determinants of the IgM antibodies

C. reducing the number of helper T cells in the body

D. reducing the number of cytotoxic cells

E. increasing the initial exposure to the antigen

A. blocking the attachment of the IgE antibodies to the mast cells

Which of the following kills invading microbes?

A. lysozymes

B. stomach acid

C. intestinal enzymes

D. all of the above

E. none of the above

D. all of the above

The immune system releases molecules of _______ that cause the redness, heat, and swelling of the inflammatory response (as well as the itching, sneezing, and runny nose of an allergic reaction).

A. histamine

B. antibody

C. adrenaline

D. antigen

E. allergen

A. histamine

B cells and T cells that do not immediately attack pathogens, but instead remain inactive until a future encounter with the pathogen, are referred to as:

A. leukocyte reservoir cells

B. memory B cells and memory T cells

C. stem B cells and stem T cells

D. residual lymphocytes

E. MHC factors

B. memory B cells and memory T cells

Helper T cells:

A. find pathogens hidden within cells.

B. lyse (break open) the cell wall of pathogens to promote apoptosis.

C. help activate B cells and T cells to undergo clonal selection and proliferation.

D. make capillaries leaky to assist the exit of neutrophils from the blood.

E. turn into cytotoxic T cells when they encounter a B cell in antigen presentation mode.

C. help activate B cells and T cells to undergo clonal selection and proliferation

The inflammatory response includes all of the following except:

A. release of histamine by mast cells

B. temperature increase

C. increased blood flow

D. phagocytosis

E. blood vessel constriction

E. blood vessel constriction

Why are measles vaccinations effective?

A. They cause the inflammation response resulting in the production of antibodies that engulf the measles virus if it enters the body.

B. They cause an immune response resulting in the production of cytotoxic T cells that remain in the blood attacking all viruses that enter the body.

C. They cause an immune response resulting in the production of memory B cells that provide a rapid response if the individual is subsequently infected by the measles virus.

D. They cause the inflammation response resulting in the production of memory T cells that provide a limited response if infected by the measles virus.

C. They cause an immune response resulting in the production of memory B cells that provide a rapid response if the individual is subsequently infected by the measles virus.