AP Bio 2020 Practice Exam 3 MCQ

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%

A population of fruit flies (Drosophila pseudoobscura) grown on a typical nutrient source was separated into several growth chambers. Each of the new chambers was assigned a different source of carbohydrates for nutrition, either starch or maltose, and maintained for many generations (Figure 1). After a year, male and female flies were paired up in different combinations. The instances of mating between the males and females grown on the same nutrient source and males and females grown on different nutrient sources were recorded (Table 1). Starch is a complex carbohydrate that is digested by the enzyme amylase. A mutation in the gene that encodes amylase prevents the digestion of starch. The inability to digest starch is an autosomal recessive trait. In a population of 1,0001,000 flies, 410410 were unable to break down starch. Which of the following is closest to the number of flies expected to be heterozygous for

0.46

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

Figure 1. Change in the population size of sea lions over time. Error bars represent ±2SEx¯. Which of the following best estimates the population size of the sea lions in 2000 based on the data shown in Figure 1?

175,000

Certain chemicals, including sodium fluoride (NaF), are capable of inhibiting specific steps of glycolysis. Figure 1 shows the steps of the glycolysis pathway, indicating where various macromolecules enter the pathway as well as the specific reaction inhibited by NaF. 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

Certain chemicals, including sodium fluoride (NaF), are capable of inhibiting specific steps of glycolysis. Figure 1 shows the steps of the glycolysis pathway, indicating where various macromolecules enter the pathway as well as the specific reaction inhibited by NaF. If NaF is added to cells undergoing cellular respiration, which of the following will most likely accumulate in the cells?

2-phosphoglycerate

A scientist is investigating the possibility that two traits in a particular plant are determined by genes that are on the same chromosome. The scientist crossed a plant that is homozygous dominant for both traits with a plant that is homozygous recessive for both traits. The heterozygous offspring in the F1F1 generation were then crossed with a plant that is homozygous recessive for both traits. The results expected if the genes independently assort and the observed results are presented in the table. Which of the following critical values should the scientist use for the chi-square analysis of the data?

7.81

Figure 1. Diagram of the cell cycle with key checkpoints 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

Lactase is the enzyme needed to digest lactose, the sugar found in milk. Most mammals produce lactase when they are young but stop once nursing ends. In humans however, many people continue to produce lactase into adulthood and are referred to as lactase-persistent. 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

High levels of certain plant nutrients in runoff can lead to rapid growth of algae (an algal bloom) in aquatic ecosystems. These algal blooms are generally followed by algal death and decomposition, which consumes large amounts of dissolved oxygen in the water and results in oxygen levels insufficient to support aerobic respiration. This process is known as eutrophication. The amount of algae present in a body of water can be estimated from the amount of chlorophyll a in a sample of the water. A researcher studying eutrophication collected samples at different times of the year in a freshwater ecosystem. The samples were analyzed for total nitrogen and chlorophyll a concentration (Figure 1) as well as total phosphorus and chlorophyll a concentration (Figure 2). 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.

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

All eukaryotes and prokaryotes contain ribosomes.

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.

Scientists investigated the effect of oxygen levels on the net rate of carbon fixation in two types of plants. The plants were grown in either well-watered soil (control) or dry soil and then exposed to either 21%21% or 1%1% O2O2. The net rate of CO2CO2 fixation for both types of plants was measured. Data are shown in Figure 11 and Figure 22. Which of the following statements about the rate of CO2CO2 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.

Melanocytes are skin cells that can become cancerous and develop into a cancer known as melanoma. Some cancerous melanocytes have developed resistance to the drugs currently used to treat melanoma. As a result, researchers are investigating the effects of a new compound (drug XX) on four different melanoma cell lines. Researchers analyzed cell survival in two cell lines (Figure 1) and oxygen consumption in the presence of drug XX in all four cell lines (Figure 2). Figure 3 shows the proposed mechanism by which drug XX affects cells. Which of the following best describes the data in Figure 1 ?

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

Melanocytes are skin cells that can become cancerous and develop into a cancer known as melanoma. Some cancerous melanocytes have developed resistance to the drugs currently used to treat melanoma. As a result, researchers are investigating the effects of a new compound (drug XX) on four different melanoma cell lines. Researchers analyzed cell survival in two cell lines (Figure 1) and oxygen consumption in the presence of drug XX in all four cell lines (Figure 2). Figure 3 shows the proposed mechanism by which drug XX affects cells. A researcher has identified a compound that reverses the effect of drug XX. Based on Figure 3, which of the following best explains how the compound acts in the pathway to reverse the effects of drug XX?

C. (sorry y'all, it's a picture)

Certain chemicals, including sodium fluoride (NaF), are capable of inhibiting specific steps of glycolysis. Figure 1 shows the steps of the glycolysis pathway, indicating where various macromolecules enter the pathway as well as the specific reaction inhibited by NaF. 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.

High levels of certain plant nutrients in runoff can lead to rapid growth of algae (an algal bloom) in aquatic ecosystems. These algal blooms are generally followed by algal death and decomposition, which consumes large amounts of dissolved oxygen in the water and results in oxygen levels insufficient to support aerobic respiration. This process is known as eutrophication. The amount of algae present in a body of water can be estimated from the amount of chlorophyll a in a sample of the water. A researcher studying eutrophication collected samples at different times of the year in a freshwater ecosystem. The samples were analyzed for total nitrogen and chlorophyll a concentration (Figure 1) as well as total phosphorus and chlorophyll a concentration (Figure 2). 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

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

Protoporphyria is a genetic disorder characterized by an extreme sensitivity to sunlight. One form of protoporphyria is caused by a mutation in the ALAS2 gene that results in the accumulation of protoporphyrin, an organic compound, in the blood, liver, and skin. The pedigree in Figure 1 shows the incidence of protoporphyria in a particular family. 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 ALAS2 alleles

Maturation promoting factor, MPFMPF, is a cyclin-CDKCDK complex that catalyzes the phosphorylation of other proteins to start mitosis. The activity level of MPFMPF is dependent on the relative concentrations of the cyclin and CDKCDK components of MPFMPF (Figure 1). 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 remains the same because DNA replication is occurring.

Newborn babies and hibernating animals contain a large amount of brown adipose (fat) tissue (BATBAT). Certain proteins in the BATBAT cells increase the permeability of the inner mitochondrial membrane to protons, disrupting the proton gradient. Which of the following best predicts the effect of disrupting the proton gradient in BATBAT?

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

Which of the following describes the most likely location of cholesterol in an animal cell?

Embedded in the plasma membrane

Two types of cells, alpha and beta cells, produce signaling molecules that affect blood sugar levels in opposite ways (Figure 1). Epinephrine is a chemical, often released during periods of exercise, that ultimately causes an increase in blood sugar levels in the body. Based on Figure 1, which of the following best explains how exercise causes blood glucose levels to rise?

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

Certain chemicals, including sodium fluoride (NaF), are capable of inhibiting specific steps of glycolysis. Figure 1 shows the steps of the glycolysis pathway, indicating where various macromolecules enter the pathway as well as the specific reaction inhibited by NaF. 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.

Certain chemicals, including sodium fluoride (NaF), are capable of inhibiting specific steps of glycolysis. Figure 1 shows the steps of the glycolysis pathway, indicating where various macromolecules enter the pathway as well as the specific reaction inhibited by NaF. 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.

A researcher measured the temperature at which two different samples of double-stranded DNADNA denature (separate into single strands). Sample 11 denatured at a significantly lower temperature than sample 22 did. Based on the data, the researcher claims that the DNADNA in sample 22 is composed of a higher percentage of guanine and cytosine than the DNADNA in sample 11 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.

A researcher is conducting an experiment in which cells in different phases of the cell cycle are fused together. The researcher then records what happens to the nuclei of the resulting cell (Table 1). Which of the following research questions is best addressed by the experiment?

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

Pesticides are chemicals that are often sprayed on crops to kill plant-eating insects, preventing damage to the crops. While pesticides are effective initially, many researchers claim that any single pesticide will see reduced effectiveness in as little as ten to fifteen years. 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.

A population of fruit flies (Drosophila pseudoobscura) grown on a typical nutrient source was separated into several growth chambers. Each of the new chambers was assigned a different source of carbohydrates for nutrition, either starch or maltose, and maintained for many generations (Figure 1). After a year, male and female flies were paired up in different combinations. The instances of mating between the males and females grown on the same nutrient source and males and females grown on different nutrient sources were recorded (Table 1). Which of the following combinations of flies showed the highest number of mating instances?

Males grown on starch paired with females grown on starch

Melanocytes are skin cells that can become cancerous and develop into a cancer known as melanoma. Some cancerous melanocytes have developed resistance to the drugs currently used to treat melanoma. As a result, researchers are investigating the effects of a new compound (drug XX) on four different melanoma cell lines. Researchers analyzed cell survival in two cell lines (Figure 1) and oxygen consumption in the presence of drug XX in all four cell lines (Figure 2). Figure 3 shows the proposed mechanism by which drug XX affects cells. Based on Figure 2, which of the following best supports the claim that drug XX 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.

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.

Protoporphyria is a genetic disorder characterized by an extreme sensitivity to sunlight. One form of protoporphyria is caused by a mutation in the ALAS2 gene that results in the accumulation of protoporphyrin, an organic compound, in the blood, liver, and skin. The pedigree in Figure 1 shows the incidence of protoporphyria in a particular family. 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

Researchers studying the bacterium Escherichia coli split a population of the bacteria into two samples. Sample 11 was transformed with a plasmid containing a gene that makes the bacteria resistant to the antibiotic kanamycin. Sample 22 was transformed with a plasmid lacking the antibiotic resistance gene. A portion of each sample was then added to growth plates containing just nutrients or growth plates containing nutrients and kanamycin. 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 grew on plate 4.

Melanocytes are skin cells that can become cancerous and develop into a cancer known as melanoma. Some cancerous melanocytes have developed resistance to the drugs currently used to treat melanoma. As a result, researchers are investigating the effects of a new compound (drug XX) on four different melanoma cell lines. Researchers analyzed cell survival in two cell lines (Figure 1) and oxygen consumption in the presence of drug XX in all four cell lines (Figure 2). Figure 3 shows the proposed mechanism by which drug XX affects cells. 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 XX?

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 pHpH is between 1.51.5 and 3.53.5, while the other functions in the small intestines, where the pHpH is between 66 and 88. 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.

Protoporphyria is a genetic disorder characterized by an extreme sensitivity to sunlight. One form of protoporphyria is caused by a mutation in the ALAS2 gene that results in the accumulation of protoporphyrin, an organic compound, in the blood, liver, and skin. The pedigree in Figure 1 shows the incidence of protoporphyria in a particular family. 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 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 reulatory sequences to block transcription.

A population of fruit flies (Drosophila pseudoobscura) grown on a typical nutrient source was separated into several growth chambers. Each of the new chambers was assigned a different source of carbohydrates for nutrition, either starch or maltose, and maintained for many generations (Figure 1). After a year, male and female flies were paired up in different combinations. The instances of mating between the males and females grown on the same nutrient source and males and females grown on different nutrient sources were recorded (Table 1). 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.

Belding's ground squirrels (Spermophilus beldingi) live in closely related groups. When they feed in the open, certain individuals (guard squirrels) watch for predators instead of feeding. The guard squirrels give an alarm call when a predator is sighted, allowing the rest of the group to run to safety. Researchers have noted that, because the alarm call draws attention to the guard, the guard is more likely to be caught by the predator and therefore has a lower survival rate in comparison with the other squirrels. 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 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.

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.

High levels of certain plant nutrients in runoff can lead to rapid growth of algae (an algal bloom) in aquatic ecosystems. These algal blooms are generally followed by algal death and decomposition, which consumes large amounts of dissolved oxygen in the water and results in oxygen levels insufficient to support aerobic respiration. This process is known as eutrophication. The amount of algae present in a body of water can be estimated from the amount of chlorophyll a in a sample of the water. A researcher studying eutrophication collected samples at different times of the year in a freshwater ecosystem. The samples were analyzed for total nitrogen and chlorophyll a concentration (Figure 1) as well as total phosphorus and chlorophyll a concentration (Figure 2). Which of the following was the dependent variable in the researcher's study?

The concentration of chlorophyll a

High levels of certain plant nutrients in runoff can lead to rapid growth of algae (an algal bloom) in aquatic ecosystems. These algal blooms are generally followed by algal death and decomposition, which consumes large amounts of dissolved oxygen in the water and results in oxygen levels insufficient to support aerobic respiration. This process is known as eutrophication. The amount of algae present in a body of water can be estimated from the amount of chlorophyll a in a sample of the water. A researcher studying eutrophication collected samples at different times of the year in a freshwater ecosystem. The samples were analyzed for total nitrogen and chlorophyll a concentration (Figure 1) as well as total phosphorus and chlorophyll a concentration (Figure 2). 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.

Many species of corals are threatened by the increasing temperatures and decreasing pHpH of ocean waters. One species, Stylophora pistillata, has been found to thrive in water that is warmer and has a lower pHpH than the water that corals typically thrive in. Additionally, researchers have found that the tolerance for the new water conditions is heritable. 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.

In pea plants, flower color and the length of the flower's pollen grains are genetically determined. Researchers studying pea plants crossed homozygous dominant pea plants with homozygous recessive pea plants. The F1 plants were then crossed, and the number of offspring with each phenotype was recorded. The researchers' observed data, however, differed from the expected data. 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.

Figure 1. Diagram of the electron transport chain and ATPATP synthase in the membrane of mitochondria 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.

A population of fruit flies (Drosophila pseudoobscura) grown on a typical nutrient source was separated into several growth chambers. Each of the new chambers was assigned a different source of carbohydrates for nutrition, either starch or maltose, and maintained for many generations (Figure 1). After a year, male and female flies were paired up in different combinations. The instances of mating between the males and females grown on the same nutrient source and males and females grown on different nutrient sources were recorded (Table 1). 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.

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

Mosquitoes are frequently a target of insect control strategies because of their ability to spread disease. One strategy is to introduce guppies, a type of freshwater fish, into areas where mosquitoes are a problem. Guppies can consume large numbers of mosquito larvae, which cuts down on the number of mosquitoes living to adulthood. Researchers assessing the effectiveness of the guppy solution are concerned that the introduction of guppies might cause more problems than it is fixing. Guppies are hardy, tolerant of a wide range of environmental conditions, and fast-reproducing. 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.

Modern bananas originated from a cross between a tetraploid banana species and a diploid banana species. The product of this cross was the triploid Cavendish banana strain, a sterile hybrid that is only grown asexually. Recently, the Panama fungus has been observed more frequently parasitizing the Cavendish banana, and scientists claim that this type of banana is on the brink of extinction. 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?

The lagging stranged 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.

A population of fruit flies (Drosophila pseudoobscura) grown on a typical nutrient source was separated into several growth chambers. Each of the new chambers was assigned a different source of carbohydrates for nutrition, either starch or maltose, and maintained for many generations (Figure 1). After a year, male and female flies were paired up in different combinations. The instances of mating between the males and females grown on the same nutrient source and males and females grown on different nutrient sources were recorded (Table 1). 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.

Protoporphyria is a genetic disorder characterized by an extreme sensitivity to sunlight. One form of protoporphyria is caused by a mutation in the ALAS2 gene that results in the accumulation of protoporphyrin, an organic compound, in the blood, liver, and skin. The pedigree in Figure 1 shows the incidence of protoporphyria in a particular family. One mutation in ALAS2 that is associated with protoporphyria is a four-nucleotide deletion. The protein expressed from the mutant allele is 2020 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.

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.

The primary function of the kidney is to exchange molecules across a membrane between the blood and the urine. One type of kidney cell has a basic rectangular shape, except for a single surface, which is lined with tiny, finger-like projections that extend into the surrounding extracellular space. 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.

Sugar gliders and Northern flying squirrels are mammals that have many morphological similarities despite being genetically different. Both are nocturnal and have large eyes to help them see in the dark. Both live in trees and have flaps of skin connecting their front and back legs, and when their front and back legs are extended, the flaps allow the animals to glide from one tree branch to another. Sugar gliders are native to Australia, and Northern flying squirrels are native to North America. Which of the following best explains the morphological similarities between these two species?

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

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.

Wolves, once native to Yellowstone National Park, were hunted to the point of complete extinction in the park. As a result, the elk population in the park flourished, putting extra demands on the carrying capacity of the park. Many other species, such as certain trees and beavers, were negatively affected by the increase in elk. Years later, wolves were reintroduced into the park. While the elk population decreased after the wolves returned, the beaver and songbird populations began to increase as did the populations of various plant species. 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.

Figure 1. Protein synthesis in a prokaryotic cell 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.