AP BIO final 😇

If 30% of the nucleotides in a single-stranded RNA molecule are adenine, then what percent are expected to be thymine?

0%

The fertilization of ovules from plant Q by pollen from plant R results in the production of seeds. What percent of the genes in each offspring's chloroplasts will have been inherited from plant R?

0%- no genetic info in chloroplast!

Assuming the population is in Hardy-Weinberg equilibrium, which of the following is closest to the frequency of carriers in the general population?

0.02430

Which of the following is closest to the number of flies expected to be heterozygous for the amylase mutation assuming all conditions of Hardy-Weinberg equilibrium are met?

0.46

A particular gene has two alleles, a dominant allele A and a recessive allele a. The frequency of allele A is 0.55. If the population is in Hardy-Weinberg equilibrium with respect to the gene, then what is the expected frequency of genotype Aa?

0.495

A researcher is crossing two organisms that are heterozygous for three Mendelian, unlinked traits (XxYyZz). Which of the following is the fraction of offspring that are predicted to have the genotype xxyyzz?

1/64

Which of the following best estimates the population size of the sea lions in 2000 based on the data shown in Figure 1?

175k

Based on Figure 1, the net number of ATP molecules produced during glycolysis from the metabolism of a single glucose molecule is closest to which of the following?

2 (2 ATP made in glycolysis)

If NaF is added to cells undergoing cellular respiration, which of the following will most likely accumulate in the cells?

2-phosphoglycerate

Lizard chi square; Which of the following values is closest to the chi-square value the scientist calculated?

23.1

The probability that individual III-5 will develop Friedreich's ataxia is closest to which of the following?

25%

Based on the data in Table 1, which of the following is the earliest time point at which there is a statistical difference in average pH between the control and treatment groups?

35 minutes

The researcher plans to do a chi-square analysis of the data and calculates the expected number of mice with each combination of phenotypes. Which of the following is the expected number of offspring that will display both trait Q and trait R?

36

Based on the data, which of the following is the best approximation of the rate of growth per week in section II from day 14 to day 21 ?

4.5g a week

Based on Table 1, which of the following percentages is closest to the solute concentration of the grape?

5.5%

Which of the following critical values should be used from the test cross?

7.81

The diploid number of chromosomes in the cell of a domesticated dog is 78. Which of the following options includes the correct number of chromosomes in a cell after each cellular process (G2 checkpoint, meiosis, and fertilization, respectively)?

78, 39, 78

Assuming that the size of the tusks is heritable, which of the following is the most likely long-term effect of poachers targeting African elephants with large tusks?

A decrease in average tusk size because elephants with large tusks are less likely to survive to reproduce

Based on the data, which of the following best describes the relationship between light and the degradation of mRNA G and mRNA H?

A longer exposure to light increases the rate of mRNA G degradation but not of mRNA H degradation.

Which of the following describes a mutation that would lead to an increase in the frequency of nondisjunction?

A mutation affecting checkpoint 3 proteins that prevents attachment of spindle fibers

Which of the following mutations is most likely to cause lactase persistence in humans?

A mutation that increases the binding of transcription factors to the promoter of the lactase gene

Which of the following best describes the production of DMSP by coral and coral symbionts?

A negative feedback mechanism that reverses the environmental change

Which of the following is the outgroup in the cladogram shown in Figure 1?

A. carolinensis

Which of the following best describes the difference between the total amount of DMSP produced by adults compared to juveniles at the start of the 32°C trial?

Adult corals produced 5 times more DMSP than juveniles produced.

Which of the following best explains the mechanism by which alanine inhibits pyruvate kinase activity?

Alanine binds to an allosteric site of the enzyme, changing the shape of the enzyme's active site.

Which of the following best explains how higher concentrations of nitrogen and phosphorus contribute to eutrophication?

Algae require nitrogen and phosphorus to build macromolecules, so higher concentrations of these nutrients can result in algal blooms.

Amylase is an enzyme that converts carbohydrate polymers into monomers. Glycogen synthase is one of the enzymes involved in converting carbohydrate monomers into polymers. Which of the following best explains the reactions of these enzymes?

Amylase aids in the addition of a water molecule to break covalent bonds whereas glycogen synthase aids in the removal of a water molecule to form covalent bonds.

Based on Figure 1, which of the following would provide the strongest evidence to support a claim that A. valencienni and A. lineatopus are the two anole species most closely related to A. sagrei ?

Analyzing homologous DNA sequences among the species

Which of the following statements about the rate of CO2 fixation in the two types of plants is supported by the data shown in the figures?

At 21% O2, plant type 2 has a lower rate of CO2 fixation than plant type 1 does in both types of soil.

Drug X; Which of the following best describes the data in Figure 1 ?

At a concentration above 10 μM, drug X reduces melanoma cell survival.

Which of the following graphs best represents the data in Table 1 ?

B- the line graph with confidence intervals

Which of the following best explains why bile salts cause the sulfur powder to sink?

Bile salts decrease the surface tension of the urine sample.

Which of the following is evidence that eukaryotes and prokaryotes share a common ancestor?

Both contain ribosomes

In anoles, small toe pads are better for gripping irregular surfaces such as the forest floor, and large toe pads are better for gripping smooth surfaces such as leaves. Based on the data in Table 1, if brown anoles are introduced into a forest where green anoles currently live, which of the following predictions about the two species is most likely?

Brown anoles will occupy a different area of the forest from green anoles which will minimize competition.

Tarui disease is an inherited disorder that is caused by mutations in PFKM, the gene that encodes a subunit of phosphofructokinase, an enzyme in the glycolysis pathway. Individuals with Tarui disease produce little or no functional phosphofructokinase in skeletal muscle cells. Based on Figure 1, which of the following best explains why a low carbohydrate diet is recommended for those with Tarui disease?

Carbohydrate metabolism requires all the reactions of glycolysis, and amino acids and fatty acids do not.

Which of the following best describes the process by which gas from the atmosphere is obtained by plants and used to build lipids?

Carbon cycle

Ethylene gas is an organic molecule that serves many cell signaling roles in flowering plants. Which of the following best explains how a positive feedback mechanism involving ethylene works?

Cells of ripening fruit produce ethylene, which activates the ripening response in other fruit cells.

Which of the following best explains the buildup of lactic acid in individuals with the mutation?

Cells undergo fermentation because pyruvate cannot be metabolized to proceed into the Krebs cycle.

Which of the following investigations would enable researchers to test the claim that an increased concentration of algae has a negative effect on the number of aquatic invertebrates in the ecosystem?

Counting the number of aquatic invertebrates at different concentrations of chlorophyll a in the water

Which of the following best explains how DCMU affected the reaction?

DMCU=Inhibitor to electron movement

Based on the information, an increase in the sea slug population would most likely be directly related to which of the following?

Decrease in crab population

A researcher claims that an individual has protoporphyria, based on a physical exam. Which of the following techniques would most likely confirm the researcher's claim?

Determining the nucleotide sequence of the individual's

Which of the following research questions would best guide an investigation of the link between the structure of the signaling molecules and the evolution of quorum sensing?

Did these species evolve from a common ancestor that used a similar signaling molecule?

Ultraviolet (UV) radiation can damage DNA by breaking weak bonds. Which of the following best explains how this occurs?

Disrupts double helix by breaking hydrogen bonds.

Based on Figure 1, which of the following describes the role of cyclin in the regulation of the cell cycle?

During M phase, the cyclin level peaks, resulting in an increased binding frequency with CDK.

Based on the data in the table, which of the following lizard species are most closely related?

ED

Based on the cladogram in Figure 1, which of the following conclusions about the evolution of the anole species is most reasonable?

Each species evolved as a result of different selective pressures.

In addition to the effect of temperature on DMSP produced by corals and their symbionts, which of the following relationships is also being considered in this experiment?

Effect of additional DMSP produced by symbionts and the corals' age

Which of the following best predicts the effect of disrupting the proton gradient in BAT?

Electron transport and oxidative phosphorylation will be decoupled, generating more heat but less ATP

Where is cholesterol in an animal cell?

Embedded in the plasma membrane

Based on the cladogram, which of the following are the traits shared between ferns and pines?

Embryo and xylem only

Which of the following best explains the connection between energy, growth, and the maintenance of an ordered system in the experiment?

Energy input from light is required for the grass to grow and maintain an ordered structure.

Which of the following most likely explains how the changing seasons result in changing fur color in an arctic fox?

Environmental factors cause changes in gene expression, resulting in seasonal variations in pigment production.

Based on Figure 1, which of the following best explains how exercise causes blood glucose levels to rise?

Epinephrine activates alpha cells, causing the release of glucagon, and inhibits beta cells, blocking the release of insulin.

Which of the following claims is most consistent with the data shown in Figure 2 ?

Esp expression is necessary to prevent the overproduction of insulin.

Figure 1 shows a model of the endocrine signaling pathway that regulates ovulation. Which of the following observations would provide evidence of a positive feedback mechanism in this system?

Estrogen from the ovaries stimulates the hypothalamus and anterior pituitary to secrete more GnRH, LH, and FSH.

What evolutionary advantage does compartmentalization of core metabolic processes offer eukaryotes?

Evolution of a nucleus in eukaryotes separates the processes of transcription and translation and they can be regulated separately.

Which of the following best describes the process by which the bacteria are breaking down the glucose to produce lactic acid?

Fermentation; bacteria are breaking down sugars in the absence of oxygen

Based on the codon chart above, which of the following amino acid changes is most likely found in the mutated protein?

Glu Val

Which of the following describes why a glucose transporter is needed to move glucose into the cell?

Glucose is large and polar and cannot pass through the phospholipid bilayer.

Based on Table 1, which of the following best explains the difference in water potential between certain solutions and the grapes?

Grape soda and NaCl have a lower water potential because these two solutions caused the grape to lose water.

Based on the data in Table 1, which of the following best explains the observed differences in cold tolerance between brown anoles (A. sagrei) and green anoles (A. carolinensis) in the United States?

Green anoles with greater tolerance for cold had greater reproductive success in areas with colder temperatures

Sample 1 denatured at a significantly lower temperature than sample 2 did. Based on the data, the researcher claims that the DNA in sample 2 is composed of a higher percentage of guanine and cytosine than the DNA in sample 1 is. Which of the following best supports the researcher's claim?

Guanine-cytosine pairs denature at a higher temperature because they have more hydrogen bonds between them than adenine-thymine pairs do.

Which of the following best explains why a cell's plasma membrane is composed of two layers of phospholipids rather than just a single layer?

Having two oppositely oriented layers of phospholipids allows only the hydrophilic heads to interact with water inside and outside of the cell.

Which of the following describes a scenario that would result in the phenotypic change shown in the graph?

House sparrows that lay smaller-than-average clutches of eggs produce fewer viable offspring, while larger-than-average clutches of eggs result in malnourished chicks that have a higher mortality rate.

A researcher is conducting an experiment in which cells in different phases of the cell cycle are fused together. Which of the following research questions is best addressed by the experiment?

How do chemical messengers affect a cell's transition between the phases of the cell cycle?

Which of the following questions will best guide a follow-up investigation about the role of pheromones in locating prey?

How do pike determine that the fathead minnow pheromone is present in the water?

Which of the following statements best describes the results seen in Figure 2 ?

Individuals III-2 and III-3 carry two different alleles of the FXN gene, a mutant allele and a wild-type allele. Individual IV-1 inherited two copies of the mutant allele.

Based on the data, which of the following organisms are most distantly related?

Insects and vertebrates

Which of the following best supports the claim by scientists that the pesticides will eventually lose their effectiveness?

Insects that are naturally resistant to the pesticide will survive and reproduce more than the insects that are sensitive to the pesticide.

Which of the following best describes the effect of insulin binding to the receptor on the osteoblast cells?

Insulin binding ultimately increases pancreatic secretion of additional insulin.

Oncogenes are genes that can cause tumor formation as a result of a particular mutation. Which of the following potential therapies would be most effective at preventing the expression of an oncogene?

Introducing a chemical that binds to transcription factors associated with the oncogene's promoter

Which of the following best explains how the extensive folding of the inner mitochondrial membrane benefits a eukaryotic cell?

It increases the area available for proteins involved in energy transfer.

Why did they use test tube 2 as a control?

It was a positive control for measuring the effect of DCMU on the reaction.

Which of the following claims is best supported by the experimental results?

Light is required for the electron transport chain to transfer electrons.

Based on the data in Figure 1, which of the following most likely represents the change in energy that occurs when ATP hydrolysis is coupled with the phosphorylation of a substrate?

Line 1 = ATP hydrolysis, and line 4 = phosphorylation of a substrate.

A researcher is studying two different species. Which of the following sets of observations would best support the claim that the two species have structural similarities as a result of convergent evolution?

Low genetic similarity, same function of structure, different form of structure.

Which of the following combinations of flies showed the highest number of mating instances?

Males grown on starch paired with females grown on starch

Which of the following best explains the observed difference in mass between the grass in section I after 14 days and the grass in section III after 21 days?

Mass lost by cell respiration in section III was not replaced by photosynthesis.

Based on Figure 2, which of the following best supports the claim that drug X inhibits oxygen consumption?

Melanoma line 3 consumes statistically less oxygen per cell in the presence of drug X than it does in the presence of the solvent alone.

Long-term exposure to extended periods of bright light after sunset is most likely to affect a person in which of the following ways?

Melatonin synthesis will be inhibited, and the person will have difficulty sleeping.

Which of the following is the strongest evidence supporting the endosymbiont hypothesis?

Mitochondria have their own DNA and divide independently of the cell.

Which of the following best describes the cellular location where pyruvate dehydrogenase is most likely active?

Mitochondria matrix

Which of the following is the most likely effect of a mutation in the gene coding for a DNA repair enzyme?

Mutations will accumulate more quickly because the cell will not be able to fix errors in replication.

Which of the following best describes the relationship between the pitcher plant and the woolly bat?

Mutualism

Which of the following best describes a characteristic of DNA that makes it useful as hereditary material?

Nucleotide bases in one strand can only be paired with specific bases in the other strand.

Climate change could affect the ecosystem of the Elkhorn Slough in many ways. From the information provided, which of the following predictions about the direct, local effects of climate change is most likely?

Ocean warming will favor population growth of nonnative species as their habitats shift northward.

Which of the following best describes the genotype of the individual identified with an asterisk in the pedigree in Figure 1 ?

One dominant ALAS2 allele and one recessive ALAS2 allele

bacteria; Which of the following claims is best supported by the data in Table 1 ?

Only the bacteria that were successfully transformed with the kanamycin resistance gene grew on plate 4.

As otters were removed during the hunting years, there was a large decrease in the catches of fish species from the eelgrass habitats. Which of the following best explains why this decrease happened?

Otters are a keystone species, so their disappearance from the area resulted in the collapse of an entire community.

Based on the information presented, which of the following best explains why the researchers measured oxygen consumption as an indicator of the effectiveness of drug x?

Oxygen accepts electrons in oxidative phosphorylation, a process necessary for melanoma cell survival.

Trypsin and pepsin are enzymes that function in different areas of the digestive tract. One functions in the stomach, where the pH is between 1.5 and 3.5, while the other functions in the small intestines, where the pH is between 6 and 8. Based on Figure 1, which of the following best describes where each enzyme functions?

Pepsin works in the stomach because the optimal pH for pepsin is acidic.

A student placed a semipermeable membrane inside a U-shaped channel with two chambers, as shown. The membrane permits the movement of water but not salt. The student wants to vary the rate of osmosis that occurs across the membrane. Which of the following experimental designs will result in the fastest net rate of water movement into chamber A?

Placing salt water in chamber A and distilled water in chamber B

Which of the following best explains why triploid bananas do not produce seeds?

Production of gametes is disrupted

Which of the following best explains the presence of prolactin in various vertebrate species?

Prolactin is a homologous hormone because it has a common origin but different functions in various species.

Which of the following best describes the inheritance pattern illustrated in Figure 1 ?

Protoporphyria has an X-linked dominant inheritance pattern.

Which of the following best describes the most likely effect of the formation of a triplex DNA structure (Figure 3) on the synthesis of the frataxin protein?

RNA polymerase is prevented from binding to the DNA, resulting in a decrease in frataxin mRNA transcription.

Which of the following best illustrates the flow of information required for the synthesis of proteins encoded in the genome of a retrovirus?

RNA->DNA->RNA->Protein

Which of the following best explains how continuity of genetic information in cells is ensured across generations?

Replication uses a parental strand of DNA as a template to create a new strand of DNA.

Which of the following best explains how the prokaryotic expression of a metabolic protein can be regulated when the protein is already present at a high concentration?

Repressor proteins can be activated and bind to regulatory sequences to block transcription.

Based on the data, which type of cell would be best suited for the lining the alveoli of the lungs, where diffusion of carbon dioxide and oxygen must occur very rapidly?

Simple squamous cells. (higher SA:volume= better for cell)

For a population to be in Hardy-Weinberg equilibrium, certain conditions must be met. Which of the following best explains a characteristic of the fly populations that meets a condition of Hardy-Weinberg equilibrium?

Since the flies were confined in chambers, they did not experience any migration, so no new alleles were introduced through migration.

Assuming a negligible pressure potential, which of the following best predicts the net movement of the small diffusible solutes and water in the second experiment (Table 2) ?

Small diffusible solutes will diffuse into the grape cells, followed by water.

Which of the following best explains why the polymerase from the species T. aquaticus is often used for PCR

T. aquaticus polymerase does not denature at high temperatures.

Which of the following best describes the hydrolysis of carbohydrates?

The addition of a water molecule breaks a covalent bond between sugar monomers.

Which of the following best explains the behavior of the guard squirrels?

The behavior of the guard squirrels increases the survival of close relatives that share the genes of the guard squirrels.

Which of the following best explains the relationship between the different bumblebee species living in the same area?

The bumblebees have undergone niche partitioning due to competition.

Which of the following describes the most direct effect of a mutation in the DNA that encodes a cell's rRNA ?

The cell's ability to properly assemble ribosomes and initiate translation will be reduced.

Which of the following best explains how some cells of an individual produce and secrete a specific enzyme, but other cells of the same individual do not?

The cells transcribe and translate different combinations of genes, leading to the production of different sets of proteins.

Replicated DNA produced after a chemical is introduced. Which of the following claims is best supported by the data?

The chemical inhibits DNA ligase.

The figure shows a phylogenetic tree of various members of the order Proboscidea, which includes modern elephants. Which of the following claims is best supported by the information in the figure ?

The common ancestor of the African elephant and the mastodon is the Palaeomastodon.

Which of the following was the dependent variable in the researcher's study?

The concentration of chlorophyll a

Which of the following describes the relationship between the amount of chlorophyll a in a water sample and the concentration of nitrogen in that sample?

The concentrations of nitrogen and chlorophyll a are directly correlated.

Which of the following statements best explains the changes seen in S. pistillata in response to the changing water conditions?

The corals' adaptation is an example of natural selection because the tolerance is in response to a changing environment and has a genetic basis.

The researchers did a chi-square analysis and calculated the chi-square value to be 5.5. Based on their calculation, the researchers would most likely conclude which of the following?

The differences between observed data and expected data are due to chance.

Which of the following most likely explains how the chromosomes circled in Figure 1 could cause a genetic disorder in the person from whom the cells were obtained?

The extra chromosome will affect the levels of RNA transcribed from certain genes and the amount of protein produced from those genes in each cell.

Which of the following claims is best supported by the data in Tables 1 and 2 ?

The flies have developed a form of behavioral preference that could lead to divergence.

Pea seeds; Which of the following best explains these results?

The genes for seed color and seed shape assort independently.

Mercurial sulfhydryl is an inhibitor of aquaporins. Which of the following is the most likely effect of adding mercurial sulfhydryl to the distilled water solution?

The grape cells will gain water more slowly because of a lack of facilitated diffusion.

A massive increase in the growth of a specific species of algae resulted in record-breaking levels of a potentially dangerous toxin being released into the water. A researcher hypothesizes that the unusual growth of this algal species was caused by an increase in water temperature. The researcher designs an experiment to test the hypothesis. Which of the following is the dependent variable in the researcher's experiment?

The growth of the algae

Which of the following predicts the most likely ecological problem that would occur if guppies are introduced into new areas to control the mosquito population?

The guppies might have no natural predators, which will result in a dramatic increase in the guppy population and an increase in competition for other native species.

Humans produce sweat as a cooling mechanism to maintain a stable internal temperature. Which of the following best explains how the properties of water contribute to this physiological process?

The high heat of vaporization of water allows the body to remove excess heat through a phase change of water from liquid to gas.

Based on the data in Table 1, which of the following best evaluates the student's hypothesis?

The hypothesis is not supported because the mass of the grape increased in the grape juice.

Which of the following provides the best explanation of the scientists' claim regarding the threat to the Cavendish banana?

The lack of genetic diversity of the Cavendish banana decreases the chance that a variation exists in the population that is immune to the fungus.

Which of the following best explains why ligase is required for DNA replication? Responses

The lagging strand cannot be replicated continuously, and ligase is needed to join the fragments.

Which of the following best explains how molecules such as O2 and CO2 can move across the membrane of a cell?

The majority of the cell membrane is nonpolar, which allows small, nonpolar molecules to freely cross

fruit flies; Which of the following best represents the null hypothesis for the experiment detailed in Figure 1 ?

The mating preferences of flies are not dependent on the nutrient source on which they are grown.

Which of the following is the most likely explanation for how a mutation in the DNA could result in the loss of the carboxyl terminus of the HBB protein?

The mutation changes a codon in the coding region of the HBB transcript to a stop codon such that translation terminates earlier than it should.

One mutation in ALAS2 that is associated with protoporphyria is a four-nucleotide deletion. The protein expressed from the mutant allele is 20 amino acids shorter than the wild-type protein. Which of the following best explains why a shortened protein is produced?

The mutation introduces a premature stop codon, causing translation to end early.

The researcher calculates a chi-square value of 7.3. Assuming two degrees of freedom, which of the following is the correct interpretation of the chi-square analysis, using a p-value of 0.05 ?

The null hypothesis should be rejected because the critical value is less than the calculated value

Which of the following is represented by the gradual increase in thickness of the arrows from the top to the bottom of Figure 1 ?

The number of signaling molecules that are produced or activated increases with each step in the pathway.

Based on the information provided, which of the following best justifies the claim that osteocalcin is a hormone?

The osteoblasts in the bone secrete osteocalcin, which causes cells in the pancreas to change their activity.

According to the data, which of the following best explains the results of the experiment?

The pH of the treatment culture was lower than the pH of the control because the chemical increased the bacterial metabolic rate.

Which of the following best explains how the phospholipid bilayer of a transport vesicle contributes to cellular functions?

The phospholipid bilayer allows the vesicle to fuse with the Golgi apparatus and the plasma membrane, allowing the exocytosis of proteins.

Which of the following best describes what happened to the otter population between 1750 and 1850?

The population lost genetic diversity as a result of a bottleneck effect.

Scientists studying a wild population of mantled howler monkeys found the average birth rate to be 0.22 and the average death rate to be 0.12. At the start of the study, the population consisted of 13 monkeys. Assuming no immigration or emigration, which of the following best describes the change in population size that will occur over the next year?

The population will increase because more monkeys are being born each year than are dying.

A researcher observes that mice from the mutant strain experience low blood sugar. Which of the following best describes the feedback mechanism in the pathway (Figure 1) causing the low blood sugar in the mutant strain?

The positive feedback of insulin production

Which of the following is a approximate null hypothesis for the student's experiment?

The presence of light has no effect on the mass of the grass.

kidney Which of the following best explains the advantage these projections provide the cell?

The projections increase the surface area-to-volume ratio of the cell, which allows for more efficient nutrient exchange with the environment

Which of the following best explains how the expression of a eukaryotic gene encoding a protein will differ if the gene is expressed in a prokaryotic cell instead of in a eukaryotic cell?

The protein will be made but will not function, because prokaryotes cannot remove introns.

Figure 1 shows the amount of product produced in an enzyme-catalyzed reaction over five minutes. Which of the following best explains how the rate of the reaction changes over time?

The rate decreases because the ratio of product to substrate increases.

Which of the following best explains why larger grapes have a different rate of water absorption per gram of mass than smaller grapes do?

The rate is slower because smaller grapes have a larger surface-area-to-volume ratio than the larger grapes do.

Which of the following observations provides the best evidence that acetyl-CoA negatively regulates pyruvate dehydrogenase activity?

The rate of the pyruvate dehydrogenase-catalyzed reaction is slower in the presence of a higher concentration of acetyl-CoA.

Which of the following best explains the morphological similarities between these two species?

The similarities between the species evolved independently as a result of similar selective pressures in each species' environment.

Which of the following most likely explains how the amino acid substitution has resulted in decreased catalytic activity by the mutated enzyme?

The substitution altered the secondary and tertiary structure of the enzyme so that the mutated enzyme folds into a different shape than the normal enzyme does.

Which of the following best describes the scientists' findings concerning the density of symbionts presented in Figure 2 ?

The symbiont density at 32°C was different from the density at 27°C on days 5 and 10 of the experiment.

Pedigree; Based on the pedigree in Figure 1, which of the following best explains the observed pattern of inheritance?

The trait is autosomal recessive, because the cross between individuals I-1 and I-2 produced an affected offspring.

Which of the following best describes a characteristic of the process shown in Figure 1 that is unique to prokaryotes?

The translation of the mRNA is occurring while the mRNA is still being transcribed.

Which of the following best explains the mechanism that maintains reproductive isolation between goats and sheep?

The two species have a different number of chromosomes, resulting in a postzygotic barrier.

Which of the following is the most likely immediate effect of an increase in runoff containing cadmium on the trophic structure of the river community?

There will be a large decrease in the trout population, resulting in an increase in damselfly nymphs.

Which of the following best explains the result of adult corals being exposed to elevated temperatures for extended periods?

They are able to obtain less energy from their symbionts because the algae have been expelled.

Based on the information provided in the passage, which of the following best describes the effect of harmful algal blooms on otter populations?

They are the density-independent factor that negatively affects the otter population regardless of its size

A mutation in the upland cotton plant causes the development of chloroplasts with a single outer membrane and no internal membranes. Which of the following would most likely be observed in chloroplasts of cotton plants with this mutation?

They would be unable to generate the ATP and NADPH needed to make sugars, because these processes occur on membranes within the chloroplast.

Which of the following best explains the most likely method by which this antitumor drug works?

Trabectedin interferes with the duplication of DNA during interphase and thus prevents cancer cells from passing the G2 checkpoint

Based on the data in the table, which of the following best explains the effects of rotenone on cellular respiration?

Treated cells are not able to break down NADH because certain enzymes of the electron transport chain are inhibited.

In which of the following tubes did the greatest reduction of DCPIP occur after 60 minutes?

Tube 2

Which of the following experimental changes would allow the scientist to observe transport of a solute across the artificial membrane?

Use a small, nonpolar solute instead of a protein

Sea turtles; Which of the following best describes the results shown in Figure 1 ?

Warmer nests produce more female sea turtles than do cooler nests.

Which of the following best explains how water is able to move upward from the roots of a plant, through its xylem in the stem, and out to the leaves?

Water and the xylem are both polar, water forms hydrogen bonds with other water molecules and the stem.

Which of the following best explains how wolves are a keystone species in this ecosystem?

Wolves help balance the population sizes of other species, allowing more species to thrive in the wolves' presence than in their absence.

Based on the data in Figure 1, which of the following best describes the inheritance pattern of Friedreich's ataxia?

autosomal recessive

The researchers performed a chi-square analysis to test their hypothesis. Assuming the researchers use a significance level of 0.05, which of the following is closest to the critical value the researchers should use in the chi-square analysis?

critical value= 3.84

An increase in the concentration of protons in the cytosol will most likely have which of the following effects on glycolysis?

glycolytic enzymes will denature as a result of the increased H+concentration.

Which of the following types of bonds is most likely responsible for the unusual base pairing shown in Figure 3 that results in the formation of a triplex DNA Structure?

hydrogen bonds

Which of the following best describes the effect of temperature on corals' ability to produce DMSP as shown in Figure 1?

juvenile and adult corals produce less DMSP at 27°C than at 32°C.

A researcher is investigating the effects of a chemical that makes thylakoid membranes permeable to hydrogen ions (H+). Which of the following is the most likely direct effect of adding the chemical to plant cells?

less ATP generated

The amino acid in Figure 1 is found in a region of a polypeptide that folds away from water. Which part of the amino acid most likely contributes to the hydrophobic behavior of this region of the polypeptide?

methyl group

Which of the following was a positive control in the experiment?

normal strain

A typical bag of fertilizer contains high levels of nitrogen, phosphorus, and potassium but trace amounts of magnesium and calcium. Which of the following best matches the fertilizer component with the molecule in which it will be incorporated by organisms in the area?

nucleic acids

Which of the following was the dependent variable in the researcher's experiment?

pH

Figure 1 shows the inheritance of a particular genetic condition in three generations of one family. Which of the following best explains the observed pattern of inheritance?

passed down by mtDNA

Which of the following samples most likely contains a double-stranded RNA virus?

sample 1

Carbon dioxide most likely enters a cell through which of the following processes?

simple diffusion through membrane

A researcher has identified a compound that reverses the effect of drug X. Based on Figure 3, which of the following best explains how the compound acts in the pathway to reverse the effects of drug X?

the compound would inhibit complex b so it's graph C, sry no picture I aint paying 3.99

On average, more ATP can be produced from an NADH molecule than can be produced from a molecule of FADH2. Based on Figure 1, which of the following best explains the difference in ATP production between these two molecules?

the electrons of FADH2 are transferred through three complexes of the electron transport chain whereas those of NADH are transferred through all four complexes.

Based on the data, which of the following is the most likely effect of a period of increased volcanic activity that significantly decreases the amount of sunlight reaching a particular ecosystem for several years?

there will be a decrease in population size

Protein X activates gene expression only in cells exposed to a specific signaling molecule. In a study, researchers determined the intracellular location of Protein X in cultured cells both before and after exposing the cells to the signaling molecule. What is protein x?

transcription factor

Which of the following observations would provide the strongest evidence that two plants belong to different biological species?

viable but sterile offspring

Which of the following best describes the role of water in photosynthesis?

water molecules donate electrons to the electron transport chain.