Chapter 43 and 44 Clicker Questions

Animals that can produce exceptionally concentrated urine should be expected to have nephrons with longer _____. 1. descending limbs of the loops of Henle 2. ascending limbs of the loops of Henle 3. distal tubules 4. proximal tubules

1 and 2

What is true of a secondary immune response? 1. It is brought about by memory cells. 2. It is less effective than a primary immune response. 3. It includes a humoral response but not a cell-mediated response. 4. After it occurs, the immune system can only respond to reinfection with the same antigen by mounting another primary immune response.

1 only

Place these groups in the order in which they appeared: 1. Porifera 2. Cnidaria 3. Aceola 4. Nematoda

1, 2, 3, 4

Consider this graph of the immune response to antigens A and B. If you expose this individual to antigen C on day 56, what do you expect to see? 10^3 antibodies to B on day 61 10^4 antibodies to A on day 61 10 antibodies to C on day 61 10 antibodies to C on day 67 10 antibodies to A on day 67

10 antibodies to C on day 67

For mice with no access to water, what is the ratio of urine osmolarity to blood osmolarity? 1:1 9:6 15:1 245:5

15:1

For mice with unlimited access to water, what is the ratio of urine osmolarity to blood osmolarity? 1:1 1:4 14:7 43:4

1:1

Blood flukes are parasitic flatworms that live in the bloodstream of the host. The worm's interstitial fluids are isoosmotic to the host's blood, so which of these is/are true? 1. The worms lack flame bulbs or have nonfunctional flame bulbs. 2. The worms have flame bulbs that are mostly active in performing osmoregulation. 3. The worms have flame bulbs that eliminate nitrogenous wastes 4. The worms have flame bulbs whose role is to eliminate excess water that enters the worm by osmosis.

3 only

Which is the correct sequence of bodily responses to increased temperature? 1. Thermostat in hypothalamus activates cooling mechanisms. 2. Body temperature decreases. 3. Body temperature increases. 4. Sweat glands secrete sweat, and blood vessels in skin dilate.

3, 1, 4, 2

What is the correct sequence in which the following occur during a primary humoral immune response? 1. B cell activation 2. helper T cell activation 3. plasma cell differentiation and proliferation 4. antibody secretion 5. presentation of antigen on class II MHC proteins

5, 2, 1, 3, 4

Five years after the introduction of the polio vaccine in 1955, the annual death rate from polio had decreased by _____. 100% 75% 50% 25%

75%

In the kidneys, which hormone is most effective at causing increased numbers of aquaporins to be present in collecting duct epithelia, and what is the source of this hormone? ADH; posterior pituitary gland aldosterone; adrenal medulla renin; kidneys aldosterone; adrenal cortex ADH; kidneys

ADH; posterior pituitary gland

In some countries in _____, fewer than 50% of infants were vaccinated for measles in 2014. South America Asia Africa North America Europe

Africa

Which is not true of the Neoproterozoic era? Soft-bodied, multicellular eukaryotes could be found. Molluscs, sponges, and cnidarians could be found. Predation existed. Animal diversity decreased. Glaciers killed most life on Earth.

Animal diversity decreased

Which animal phylum has greater complexity (measured by yi) than Urochordata? Echinodermata Annelida Arthropoda All phyla are equally complex.

Annelida

Given that adult penguins don't grow from year to year, how would you explain the finding in the previous question? For several months after hatching, penguin chicks use a large proportion of the energy available to them to grow. At certain times, penguins use up their fat stores, losing considerable weight. During the breeding season, penguins produce new biomass when they lay eggs and feed their chicks. At certain times, penguins store considerable energy as fat, putting on weight in the process.

At certain times, penguins store considerable energy as fat, putting on weight in the process.

Which of the following is not an example of physical laws influencing animal body plan with respect to maximum permissible size? The thickness of vertebrates' internal skeletons increases with body dimensions. The fraction of body mass representing muscle increases with body dimensions. Insects and other arthropods require thicker external skeletons as their body dimensions increase. At no point do increased body dimensions place a limit on mobility.

At no point do increased body dimensions place a limit on mobility.

Which correctly describes phylogenetic relationships among birds, mammals, and reptiles? Birds share the closest common ancestor with dinosaurs. Reptiles and birds, but not mammals, are amniotes. Mammals evolved from therapsid reptiles after the fall of the dinosaurs. Birds and mammals are more closely related to each other than either group is to crocodilian reptiles. Among living species in the group we call reptiles, turtles and snakes are most closely related to each other.

Birds share the closest common ancestor with dinosaurs

Assume that a decrease in trypanosome abundance indicates an effective immune response. What is the best explanation for the experimental results shown in this graph? By the time the host developed an immune response to one glycoprotein, the parasite had changed to a different glycoprotein. The host was infected by new parasites three times during the course of the study. The immune response went through cycles of strength and weakness. The parasite went through regular cycles of reproduction followed by death.

By the time the host developed an immune response to one glycoprotein, the parasite had changed to a different glycoprotein

A difference between class I MHC and class II MHC molecules is _____. most body cells have class I and class II MHC molecules, but antigen-presenting cells have only class II only class I MHC molecules are important for recognition of antigen-presenting cells CD4 protein on helper T cells binds class II MHC molecules on the antigen-presenting cell class II MHC molecules interfere with effector cell production only class I MHC molecules are displayed on cell surfaces; class II MHC molecules are subcellular molecules

CD4 protein on helper T cells binds class II MHC molecules on the antigen-presenting cell

You are dissecting an unidentified animal. It is radially symmetric and has no body cavity. To what phylum might it belong? Cnidaria Chordata Platyhelminthes Annelida Arthropoda

Cnidaria

Which taxonomic level contains the other choices? Deuterostomia Lophotrochozoa Ecdysozoa Eumetazoa

Eumetazoa

In mammals, brown fat in the neck and shoulder area is specialized for rapid heat production. Which of the following is a correct statement about brown fat? It represents about 95% of total body weight in human infants. Extra mitochondria in brown fat produce its characteristic color. Brown fat has recently been detected in hibernating mammals. Individuals in warm environments have increased amounts of brown fat.

Extra mitochondria in brown fat produce its characteristic color.

Which of the following statements comparing osmoregulation in marine and freshwater bony fishes is incorrect? Freshwater fishes excrete salt ions and larger amounts of water in dilute urine than marine fishes. Freshwater fishes take in salt ions by means of their gills, while marine fishes excrete salt ions from their gills. Freshwater fishes gain osmotic water through their gills and body surfaces, while marine fishes lose osmotic water the same way. Freshwater fishes drink seawater to obtain water and salt ions, while marine fishes drink almost none.

Freshwater fishes drink seawater to obtain water and salt ions, while marine fishes drink almost none.

Which is not a reason for the rise in the diversity of animal phyla during the Cambrian? Predators acquired novel adaptations. Prey species acquired new defenses. An increase in atmospheric oxygen permitted larger bodied animals to thrive. ​Hox genes facilitated the evolution of new forms. Global cooling triggered shifts in animal lineages.

Global cooling triggered shifts in animal lineages.

Which of the following is a correct statement about hypersensitivity reactions? Hypersensitivity reactions involve antibodies of the IgG class. Platelets in connective tissues may be recruited. Hypersensitivity reactions are exaggerated allergic reactions. An acute response is called toxic shock syndrome. Histamine drugs may diminish symptoms.

Hypersensitivity reactions are exaggerated allergic reactions.

Which statement misdescribes the lateral line system? It can be found in aquatic gnathostomes. It is used in digestion. Lateral line organs form a row along each side of the body. Lateral line organs are sensitive to vibration.

It is used in digestion.

How does the renin-angiotensinogen-aldosterone system (RAAS) respond in the case of an excessive loss of both salt and body fluids? It activates the hormone atrial natriuretic peptide, which increases blood volume and pressure. It responds to the drop in blood volume and pressure by increasing water and Na+ reabsorption. It stimulates the production of ADH in the posterior pituitary, lowering blood Na+ concentration. It inhibits the production of angiotensin converting enzyme (ACE), suppressing the production of angiotensin II.

It responds to the drop in blood volume and pressure by increasing water and Na+ reabsorption.

What is "matched" between donor tissue and recipient in order to increase the likelihood of a successful transplantation? antigens allergens Toll-like receptors MHC proteins antibodies

MHC proteins

Which of the following is not associated with the production of urine? proximal tubule loop of Henle distal tubule collecting duct Malpighian tubules

Malpighian tubules

Which of the following is not an adaptation of the vertebrate kidney to diverse environments? In mammals, the juxtamedullary nephrons can concentrate urine, allowing mammals to eliminate waste without losing excess water. In birds, the nephrons have loops of Henle that don't extend as far into the medulla as those of mammals. In reptiles, the kidneys have only cortical nephrons and produce urine that is iso- or hypoosmotic to body fluid. Freshwater fishes have kidneys containing many nephrons and produce filtrate at a high rate. Marine bony fishes have more and larger nephrons than freshwater fishes, and their nephrons also lack a proximal tubule.

Marine bony fishes have more and larger nephrons than freshwater fishes, and their nephrons also lack a proximal tubule.

Which is a member of the Bilateria? Porifera Nematoda Cnidaria Ctenophora

Nematoda

You are dissecting an unidentified animal. It is bilaterally symmetric and has no body cavity. To what phylum might it belong? Cnidaria Chordata Platyhelminthes Annelida Arthropoda

Platyhelminthes

Which statement about Hox genes would lose points on a test? The Hox gene family underwent a series of duplications. Most animals share a unique homeobox-containing family of genes. ​Hox genes regulate the formation of the anterior-posterior axis. Simple animals such as sponges possess Hox genes.

Simple animals such as sponges possess Hox genes.

Which of the following is an incorrect statement about triethylamine oxide (TMAO) in sharks? Added to body fluids, TMAO combines with other compounds and solutes to raise tissue osmolarity. The presence of TMAO makes water enter the shark's body slowly by osmosis. TMAO protects cellular proteins from denaturation. TMAO is inorganic. TMAO counteracts the effects of urea.

TMAO is inorganic.

Which of the following statements regarding the nervous system's transmission of signals is false? Information is conveyed by the particular pathway the signal takes. Communication usually involves more than one type of signal. The effects can be long lasting. Transmission is extremely fast for directing rapid responses to the environment. Impulses can act on neurons, muscle cells, and cells or glands that produce secretions.

The effects can be long lasting.

How does double-stranded RNA in insects trigger antiviral defense? The binding of recognition proteins to cell wall molecules activates the Toll receptor, which secretes antimicrobial peptides that kill viruses. The enzyme Dicer-2 cuts the replicated viral RNA into fragments, and a second enzyme, Argo, inactivates it. Toll-like receptor proteins bind to fragments characteristic of the different pathogens, producing signals that initiate specific antimicrobial responses. Circulating complement proteins are activated by substances on viral surfaces, unleashing a lytic cascade.

The enzyme Dicer-2 cuts the replicated viral RNA into fragments, and a second enzyme, Argo, inactivates it.

Does the penguin or the mouse expend a greater proportion of its energy budget on thermoregulation? Why?

The mouse expends a greater proportion of its energy budget on thermoregulation because of its small size.

How much more energy does the penguin expend each year compared to the similarly sized python? The penguin expends 2 times as much energy as the python. The penguin expends 42.5 times as much energy as the python. The penguin expends 85 times as much energy as the python. The penguin expends 332,000 times as much energy as the python.

The penguin expends 42.5 times as much energy as the python

Why does the pie chart for the python include growth but not thermoregulation? The python grows throughout its life, but it does not thermoregulate. Only four variables can be shown in a pie chart, and growth is more important than thermoregulation in a python's energy budget. The python grows throughout its life, and it is an ectotherm. Energy used for hermoregulation could not be measured for the python.

The python grows throughout its life, and it is an ectotherm.

Suppose that the mice with unlimited access to water produced more urine than the mice given no access to water. How would that difference in urine production affect your ratio calculations for the two groups? (Remember that the ratio is urine osmolarity divided by blood osmolarity.) The ratios for both groups would increase. The ratio for the mice given no access to water would increase. The ratio for the mice with unlimited access to water would increase. The ratios for both groups would decrease. The ratios for both groups would stay the same.

The ratios for both groups would stay the same.

In whales and most other mammals, evolutionary adaptations that enable sufficient exchange with the environment are specialized structures that in most cases lie within the body and are branched or folded. Which of the following is not an example of this? The finger like projections in the lining of the small intestine expand the surface area. The surface of the kidney contains long, narrow blood vessels packed into ball-shaped structures. The sponge-like construction in the lung provides an expansive, wet surface for gas exchange. The internal exchange surfaces for digestion, respiration, and circulation each have an area many times that of the skin. The shape of a parasitic tapeworm places most cells of the worm in direct contact with its environment.

The shape of a parasitic tapeworm places most cells of the worm in direct contact with its environment.

Which of the following statements about atrial natriuretic peptide (ANP) is incorrect? The walls of the heart release ANP in response to a decrease in blood volume and pressure. ANP inhibits the release of renin from the juxtaglomerular apparatus (JGA). ANP inhibits the reabsorption of NaCl by the collecting ducts. ANP reduces aldosterone release from the adrenal glands. The regulatory role of ANP is under investigation.

The walls of the heart release ANP in response to a decrease in blood volume and pressure.

Why did mRNA from a diabetes insipidus patient with two mutant aquaporin-2 alleles produce nonfunctional aquaporin water channels when expressed in frog oocytes? Oocytes do not have aquaporin water channels. Foreign mRNA cannot be translated into functional protein in frog oocytes. Since frogs are aquatic, they are isoosmotic to their environment and unresponsive to aquaporin water channels. The water channels were nonfunctional because they were translated from mRNA transcribed from mutant aquaporin genes.

The water channels were nonfunctional because they were translated from mRNA transcribed from mutant aquaporin genes.

How does blood osmolarity compare between the two treatment groups? Blood osmolarity is much higher in the mice with unlimited access to water. Blood osmolarity is much higher in the mice given no water. There is little difference in blood osmolarity between the two groups of mice.

There is little difference in blood osmolarity between the two groups of mice.

How does urea concentration in blood compare between the two treatment groups? Urea concentration in blood is much higher in the mice with unlimited access to water. Urea concentration in blood is much higher in the mice given no water. There is little difference in urea concentration in blood between the two groups of mice.

There is little difference in urea concentration in blood between the two groups of mice.

When early systematists distinguished cartilaginous fishes from bony fishes, it was not clear when bony skeletons first appeared. What suggests that bony skeletons came first, followed by cartilaginous ones? All fishes except cyclostomes have jaws. Chondrichthyes and Osteichthyes have paired fins and lateral lines. Traces of bone tissue are found in living and fossil Chondrichthyes. The cartilage skeleton of Chondrichthyes is impregnated with calcium. Chondrichthyes do not have swim bladders, as do many Osteichthyes.

Traces of bone tissue are found in living and fossil Chondrichthyes.

Which of the following is a correct statement about Tregs? Tregs prevent the immune system from reacting to self-antigens. Tregs are a type of effector T cells. Tregs are a type of helper T cell. Tregs are antibody-producing cells. Tregs may cause autoimmune disorders such as rheumatoid arthritis.

Tregs prevent the immune system from reacting to self-antigens.

Without considering the sizes of the wedges, how do the three pie charts differ in which functions they include? Unlike the penguin and mouse charts, the python chart includes growth but does not include thermoregulation. Unlike the mouse and python charts, the penguin chart does not include reproduction. The python chart is the only one that includes activity. The penguin chart is the only one that includes thermoregulation.

Unlike the penguin and mouse charts, the python chart includes growth but does not include thermoregulation.

How does urea concentration in urine compare between the two treatment groups? Urea concentration in urine is much higher in the mice with unlimited access to water. Urea concentration in urine is much higher in the mice given no water. There is little difference in urea concentration in urine between the two groups of mice.

Urea concentration in urine is much higher in the mice given no water.

The table shows the data from the experiment. How does urine osmolarity compare between the two treatment groups? Urine osmolarity is much higher in the mice with unlimited access to water. Urine osmolarity is much higher in the mice given no water. There is little difference in urine osmolarity between the two groups of mice.

Urine osmolarity is much higher in the mice given no water.

By comparing these ratios, what conclusion can you draw about the sandy inland mouse? When provided with unlimited access to water, the mice produce highly concentrated urine. With no access to water, the mice produce highly concentrated urine. The mice always produce highly concentrated urine, no matter how much water they have access to. With no access to water, the mice produce highly concentrated blood.

With no access to water, the mice produce highly concentrated urine.

Later, antibodies specific for different glycoproteins were discovered. Does the data in this graph support the hypothesis that the parasite switched surface glycoproteins once the host immune system responded to the original glycoprotein? Yes. The data suggest that theparasite first displayed glycoprotein B, then glycoprotein A, and then a third glycoprotein. Yes. The data suggest that the parasite first displayed glycoprotein A, then glycoprotein B, and then a third glycoprotein. No. The data suggest that the parasite consistently displayed glycoprotein B. No. The data suggest that the parasite consistently displayed glycoprotein A.

Yes. The data suggest that the parasite first displayed

Does this data set provide evidence of homeostatic regulation? No; the blood osmolarity and urea concentration in urine are about the same in the mice with unlimited access to water. Yes; the blood osmolarity is about the same in the two treatment groups, but the urine osmolarity is not. No; there is little difference in urea concentration in blood between the two treatment groups. Yes; the urine osmolarity is greater than the urea concentration in urine in both treatment groups.

Yes; the blood osmolarity is about the same in the two treatment groups, but the urine osmolarity is not.

For our bodies and those of most other animals, increasing the number of cells decreases the ratio of outer surface area to total volume. What features of even the largest of animal bodies allow all cells access to oxygen, nutrients, and other resources? Specialized structures that may be extensively branched or folded enable exchange with the environment. In organisms with body plans that are more complex than hydra or tapeworm, harmless bloodborne microorganisms provide exchange surfaces for nutrient and gas transfer to body cells. Internal body fluids, such as interstitial fluid, link surfaces for nutrient and gas exchange to body cells. a and c a and b

a and c

Which characterize(s) an animal body plan? symmetry tissues body cavity a and c a, b, and c

a, b, and c

What percent of the mouse's energy budget goes to basal metabolism? about 15% about 20% about 25% about 40%

about 25%

Acclimatization differs from adaptation in that _____. adaptation is a temporary change during an animal's lifetime acclimatization is when internal conditions are brought into alignment with external variables such as altitude changes acclimatization only refers to changes in kidney function acclimatization always alters homeostasis

acclimatization is when internal conditions are brought into alignment with external variables such as altitude changes

What percent of the penguin's energy budget is for activity? about 10% about 35% almost 50% almost 100%

almost 50%

If you discovered a fossil that fit between the crocodilians and pterosaurs, what feature would it probably have? feathers amniote eggs fins wings milk

amniote eggs

Early vertebrate fossils called conodonts can be identified by all of the following features except _____. an internal skeleton composed of cartilage large eyes for locating prey barbed hooks at the anterior end of their mouths slender, jawless bodies an inner ear with two semicircular canals

an inner ear with two semicircular canals

Scientists researching the origins of multicellularity compared domains of _____ proteins of unicellular organisms with those of certain animals. fibrillin collagen elastin cadherin keratin

cadherin

Which genetic change is thought to have led to the increasing complexity of the arthropod body plan? increased number of Hox genes for body segmentation changes in regulation of Hox genes for body segmentation increased number of Hox genes for appendages changes in regulation of Hox genes for appendages increased complexity in genes for exoskeleton arrangements

changes in regulation of Hox genes for body segmentation

The redness of the skin of a sunburned person is the result of vasodilation of the small arteries in the skin. The skin remains red when the sunburned person is not visibly sweating. At times when a sunburned person is not sweating, heat is being transferred from the person into the air mostly by which of the following? (Hint: Heat transfer is more effective by this means when the person is running or is in a strong breeze.) radiation convection conduction evaporation absorption

convection

Archaeopteryx differed from modern birds in that it _____. had feathered wings flew well at high speeds could not take off from a standing position had airfoil wings with contoured feathers

could not take off from a standing position

Which of the following is required to activate a cell-mediated or humoral immune response to a foreign molecule? cytokines secreted by helper T cells perforins secreted by cytotoxic T cells granzymes secreted by cytotoxic T cells antibodies secreted by plasma cells complement proteins secreted by the liver

cytokines secreted by helper T cells

What should animals with radial symmetry be better able to do than those with bilateral symmetry? move quickly in one direction detect threats from above or below equally well deal effectively with food distributed homogeneously in all directions focus attention in a single direction

deal effectively with food distributed homogeneously in all directions

One reason that misinformation about vaccine safety and disease susceptibility is a societal concern is that _____. unvaccinated people carry smallpox side effects of vaccination are increasing declines in vaccination rates may result in disease outbreaks diseases like measles kill nearly five million people annually theme parks may harbor resistant strains

declines in vaccination rates may result in disease outbreaks

Suppose you traveled back to the Neoproterozoic in a time machine. What would the fauna be like compared to today? basically the same different due to the addition of extra groups different due to the absence of the bilateria Not enough is known about that time to answer this question.

different due to the addition of extra groups

A newly developed blood test can determine every virus an individual has ever encountered. This test utilizes all of the following except _____. differential centrifugation DNA sequencing bacteriophages antibody recognition peptide display

differential centrifugation

Recent research on mice identified two sets of neurons located in the hypothalamus of the brain that regulate thirst. Experimentally stimulating one set of neurons caused the mouse to _____ even if it was fully hydrated, and stimulating the other set stopped water consumption in _____ animals. stop drinking; partially hydrated drink intensely; thirsty stop drinking; dehydrated drink intensely; dehydrated stop drinking; partially hydrated

drink intensely; dehydrated

The standard metabolic rate (SMR) of an American alligator is less than 1/20th the energy used by a comparably sized adult human. One conclusion that can be drawn from this statement is that _____. ectothermy has a higher energetic requirement than endothermy changes in the environmental temperature have no effect on metabolic rate standard metabolic rate must be measured under a comfortable temperature range ectothermy has a lower energetic requirement than endothermy

ectothermy has a lower energetic requirement than endothermy

Which of the following triploblastic organisms is incorrectly paired with its body cavity classification? flatworm—pseudocoelomate earthworm—coelomate planarian—acoelomate

flatworm—pseudocoelomate

What does a correlation coefficient measure? the degree of complexity in an organism how much DNA two organisms share how two data sets are related how similar limbs are the number of genes in the nuclei of different animals

how two data sets are related

Under which circumstance should reabsorption of water from the kidney filtrate back into the bloodstream be most effective? if neither ADH nor aldosterone is present in circulation if both ADH and aldosterone are present in circulation if ADH, but not aldosterone, is present in circulation if aldosterone, but not ADH, is present in circulation if renin, angiotensin II, and aldosterone are present in circulation, but not ADH

if both ADH and aldosterone are present in circulation

What effect would you expect the drug furosemide, which blocks transport of Na+ and Cl- in the ascending limb of the loop of Henle, to have on urine volume? increase urine volume decrease urine volume no effect on urine volume

increase urine volume

In which type of cleavage pattern does each cell have the capacity to develop into a complete embryo? determinate cleavage indeterminate cleavage spiral cleavage none of the above

indeterminate cleavage

Barrier defenses are important for protection against infections by all of the following except _____. intracellular parasites fungi bacteria viruses

intracellular parasites

The river otter is a regulator rather than a conformer with regard to the environmental variable temperature because _____. it allows its internal condition to vary in accordance with external changes it uses internal mechanisms to control internal change in the face of external fluctuation it uses internal mechanisms to control internal change in the face of internal fluctuation Its internal solute concentrations may be kept constant but internal temperature may change in response to fluctuations in the ocean's temperature

it uses internal mechanisms to control internal change in the face of external fluctuation

Which organism, a human or a kangaroo rat (a desert rodent), derives a greater percentage of its total water from metabolism? Which do you think has a longer loop of Henle? kangaroo rat; kangaroo rat human; kangaroo rat kangaroo rat; human human; human

kangaroo rat; kangaroo rat

Which chordate group has all four key chordate characteristics as an adult, not just as an embryo? lancelets tunicates frogs humans

lancelets

Which of the following is characteristic of herpesvirus infections? increased antigenic variation latency direct attack on the immune system cause liver cancer not affected by stress

latency

Which defensive chemical is improperly matched with its function? perforins—lysis antibodies—pathogen neutralization histamines—dilate capillaries cytokines—immune cell stimulation lysozymes—cause fevers

lysozymes—cause fevers

Which is the closest living group to the primates? birds reptiles monotremes amphibians There is not enough information to decide.

monotremes

Which trait is shared by all vertebrates except cyclostomes at some point in development? notochord vertebrae cartilaginous skeleton cranium (head) mouth with jaws

mouth with jaws

Men who overuse synthetic testosterone (as in anabolic steroids) may experience testicular atrophy, reduced sperm count, and low levels of circulating FSH. The physiological explanation for these observations is _____. that synthetic testosterone is not as effective as natural testosterone negative feedback positive feedback that such men have inadequate numbers of FSH receptors that such men have inadequate numbers of testosterone receptors

negative feedback

Which of the following in vertebrates has the same function as hemocytes in insects? Toll like receptor interferon complement system neutrophils mast cells

neutrophils

The glycoproteins covering a trypanosome's surface are encoded by a gene that is duplicated more than a thousand times in the organism's genome. Each copy is slightly different. The number of trypanosomes was measured in 100 patients during the first few weeks of infection. What is the dependent variable in this experiment? time number of trypanosomes volume of blood number of patients

number of trypanosomes

For the eighth observation (i = 8), identify the animal phylum, xi, and yi. phylum Cephalochordata; xi = 33; yi = 68 phylum Urochordata;xi = 77; yi = 25 phylum Porifera;xi = 5.8; yi = 25 phylum Urochordata;xi = 25; yi = 77

phylum Urochordata;xi = 25; yi = 77

A synonym for an effector B cell is a(an) _____ cell. plasma memory tolerant immune suppressor

plasma

Osmoregulation is the _____. enhancement or amplification of an effect by its own influence on the process that gives rise to it movement of ions or molecules across a cell membrane into a region of higher concentration, assisted by enzymes and requiring energy process by which animals control solute concentrations and balance water gain and loss process that cells and viruses use to regulate the way that the information in genes is turned into gene products

process by which animals control solute concentrations and balance water gain and loss

Which of the following is not a key factor affecting metabolic rate? age activity level size race environmental temperature

race

The exceptionally large diversity of antigen receptors found on B cells and T cells is mostly the result of _____. random mutations clonal selection alternate splicing recombinase activity gene duplication

recombinase activity

Which group soon outcompeted amphibians on land due to their watertight skin and eggs? birds mammals reptiles cyclostomes none of the above

reptiles

Which of the following organ systems is incorrectly matched with its function? digestive—food processing (ingestion, digestion, absorption, elimination) skeletal—protection against mechanical injury, infection, dehydration, thermoregulation muscular—locomotion and other movement excretory—disposal of metabolic wastes, regulation of osmotic balance of blood nervous—coordination of body activities, detection of stimuli and formulation of responses to them

skeletal—protection against mechanical injury, infection, dehydration, thermoregulation

Which osteichthyan structure allows bony fishes to control their buoyancy using gases from their blood? operculum lateral line system swim bladder cloaca

swim bladder

Which animals are being studied as examples of an adaptation called anhydrobiosis? tardigrades polar bears cestodes ​Pseudomys hermannsburgensis camels

tardigrades

Which animal expends the most kilocalories per year on thermoregulation? the mouse the penguin the python

the penguin

The specificity of a particular antibody for its target epitope is determined by _____. The variable regions The constant regions the light chains the heavy chains the transmembrane region

the variable regions

The glycoproteins covering a trypanosome's surface are encoded by a gene that is duplicated more than a thousand times in the organism's genome. Each copy is slightly different. The number of trypanosomes was measured in 100 patients during the first few weeks of infection. What is the independent variable in this experiment? time number of trypanosomes volume of blood number of patients

time

Which two solutes become more abundant in the kidney medulla's interstitial fluid as one progresses deeper into the medulla, and what is the significance of these two gradients? urea and NaCl; interstitial fluids there become isoosmotic to blood NaCl and KCl; this promotes maximal chloride ion retention HCO3- and H+; this produces pH-neutral interstitial fluids urea and KCl; less urea is actually excreted than is possible urea and NaCl; this promotes better retention of water

urea and NaCl; this promotes better retention of water