unit 8 bio
Based on the results of the study, which of the following is the most likely connection between behavior and evolutionary fitness in a nearshore coral reef environment? A) Rays that search for food alone at low tide typically grow to larger sizes than do rays that search for food in groups. B) Rays that join groups during rising tides are reproductively more successful than are rays that do not join groups. C) Rays that swim far from shore at high tide often encounter a greater variety of species than do rays that remain near the shore. D) Rays that roam across large distances during falling tides become stronger swimmers than do rays that spend more time at rest.
B
In addition to the effect of temperature on DMSPDMSP produced by corals and their symbionts, which of the following relationships is also being considered in this experiment? A) Effect of varying light levels and coral species B) Effect of additional DMSPDMSP produced by symbionts and the corals' age C) Effect of age and varying light levels D) Effect of coral species and additional DMSPDMSP produced by symbionts
B
The data in the graph best support which of the following claims? A) Environmental contamination elevates total testosterone oxido-reductase activity in females. B) Environmental contamination reduces total testosterone oxido-reductase activity in females. C) Environmental contamination elevates total testosterone oxido-reductase activity in males. D) Environmental contamination reduces total testosterone oxido-reductase activity in males.
B
The most probable cause for the difference in mean stem length between plants in dish A and plants in dish B is which of the following? A) Shortening of cells in the stem in response to the lack of light B) Elongation of seedlings in response to the lack of light C) Enhancement of stem elongation by light D) Genetic differences between the seeds
B
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? A) The population of Cladophora will decrease, resulting in an increase in the trout population. B) There will be a large decrease in the trout population, resulting in an increase in damselfly nymphs. C) Increased stream volume will provide more area for the trout to reproduce, causing a large increase in the population of algae. D) The population of trout will decrease because the population of damselfly nymphs will decline.
B
Which of the following is the most likely result at the completion of the project? A) The biomass of coyotes will be 6 kg, and the biomass of hawks will be 0.5 kg. B) The biomass of coyotes will be dramatically reduced. C) The coyotes will switch prey preferences and outcompete the hawks. D) There will be 50 percent fewer voles and 90 percent fewer hawks.
B
Based on the information provided in the passage, which of the following best describes the effect of harmful algal blooms on otter populations? A) They are a density-dependent factor that increases otter mortality in larger populations. B) They are a density-dependent factor that reduces otter numbers at lower population sizes. C) They are a density-independent factor that negatively affects the otter population regardless of its size. D) They are a density-independent factor that increases otter mortality in only larger populations.
C
Long-term exposure to extended periods of bright light after sunset is most likely to affect a person in which of the following ways? A) Melatonin synthesis will be increased, and the entire sleep-wake cycle will be shifted by several hours. B) Melatonin synthesis will be increased, and the person will quickly fall asleep. C) Melatonin synthesis will be inhibited, and the person will have difficulty sleeping. D) Melatonin synthesis will be inhibited, and the person will quickly fall asleep.
C
One model of a sustainable fisheries practice is for individual fish to be removed from a natural population at a rate equal to the highest possible growth rate of an ideal population. The graph above represents a population of bluefin tuna living along the Atlantic coast. At which labeled point in the graph is the population growth rate the highest? A) I B) II C) III D) IV
C
Which of the following best describes the difference between the total amount of DMSPDMSP produced by adults compared to juveniles at the start of the 32°C trial? A) Adult corals produced 3 times more DMSPDMSP than juveniles produced. B) Adult corals produced 3 times less DMSPDMSP than juveniles produced. C) Adult corals produced 5 times more DMSPDMSP than juveniles produced. D) Adult corals produced 5 times less DMSPDMSP than juveniles produced.
C
Which of the following best estimates the population size of the sea lions in 2000 based on the data shown in Figure 1? A) 100,000 B) 125,000 C) 175,000 D) 285,000
C
Which of the following best explains the result of adult corals being exposed to elevated temperatures for extended periods? A) They are able to obtain more energy from their symbionts because the algae are receiving more light. B) They are able to obtain more energy from their symbionts because the efficiency increases slightly over time. C) They are able to obtain less energy from their symbionts because the algae have been expelled. D) They are able to obtain less energy from their symbionts because more DMSPDMSP is being produced at lower temperatures.
C
Which of the following changes to the environment will most likely lead to more energy entering the meadow community represented above? A) Increasing the number of nesting sites for hawks and owls B) Removing squirrels from the area C) Increasing the light available to the plants D) Applying a chemical pesticide that is specific for spiders
C
Which of the following data would be most helpful in predicting possible disruptions to the relationship between the predator and its prey? A) Time of day, because as days become shorter, nighttime hunting increases B) Average birth weight of predators, because heavier offspring will begin hunting at younger ages C) Numbers of additional predator species, because additional predators will increase competition for prey D) Prey metabolic rates, because predators are less successful against prey with higher metabolic rates
C
The researchers discovered that both species of garter snakes feed almost exclusively on amphibians found in or near the pond. Based on the results of the investigation, which of the following is most likely to occur if the amphibians become a limited source of food? A) Individuals of T. atratus will no longer prefer to be near the water. B) T. sirtalis will shift its food preference to herbivory. C) The reproduction rate of T. sirtalis will increase. D) The population size of T. atratus will decrease.
D
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? A) The grass in section III required more energy for metabolic processes than the grass in section I. B) The grass in section III performed more photosynthesis than the grass in section I. C) Only the grass in section III used energy from the seed for growth and development. D) Mass lost by cell respiration in section III was not replaced by photosynthesis.
D
Which of the following is an appropriate null hypothesis for the student's experiment? A) The absence of light negatively affects the mass of the grass. B) An increase in light promotes grass growth. C) A change in light intensity changes the rate of grass growth. D) The presence of light has no effect on the mass of the grass.
D
Which of the following statements best predicts the effect of increased cottonwood growth on the food web? A) Increased cottonwood growth will lead to an increase in the number of primary consumers, resulting in more competition between kestrels and sparrows for food. B) Increased cottonwood growth will decrease the habitat available for lizards, resulting in a decline in the number of kestrels. C) Increased cottonwood growth will provide more resources for cicadas, resulting in an increase in the kestrel population. D) Increased cottonwood growth will lead to a large accumulation of dead wood that serves as fuel for wildfires, resulting in the collapse of the food web.
C
The difference in carrying capacity between the two species when cultured separately is closest to which of the following values? A) 0 individuals per 5.0 mL B) 60 individuals per 5.0 mL C) 150 individuals per 5.0 mL D) 350 individuals per 5.0 mL
D
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? A) Ocean warming will favor population growth of nonnative species as their habitats shift northward. B) Ocean warming will decrease eelgrass habitat area as a result of increased herbivory by nonnative species. C) Harmful algal blooms will decrease otter populations as a result of increased mortality of otter prey species. D) Harmful algal blooms will decrease the availability of nutrients for eelgrass and other algae species.
A
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? A) There will be a decrease in the population sizes of most species and a decrease in the number of trophic levels. B) The population sizes of plant species will stay the same, but the average biomass of individual plants will increase. C) There will be an increase in the population sizes of omnivores because they can eat other animals instead of the plants. D) The biodiversity of the ecosystem will increase as new niches arise and become occupied by new species.
A
A researcher proposes that the spawning behavior takes place when the nighttime tides are highest during the month. Which of the following pieces of evidence would best support the researcher's claim? A) Grunion spawning occurs every two weeks during the spawning season. B) Grunion spawning occurs when nighttime illumination levels are the lowest. C) High tide occurs one time per lunar cycle. D) The light intensity of the moon varies within the lunar cycle.
A
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? A) Brown anoles will occupy a different area of the forest from green anoles which will minimize competition. B) Brown anoles will mostly prey on flying insects, and green anoles will prey on worms and grubs. C) Brown anoles and green anoles will evolve to have the same size toe pads because they share the same niche. D) Green anoles are better adapted to the forest habitat and will chase away the introduced brown anoles.
A
The food web represented above does not include bacteria and fungi. Which of the following best describes a consequence of having no bacteria and fungi in the food web? A) Grasses will have no direct access to chemical components recycled from dead organisms. B) Rabbits will have no direct access to energy absorbed from secondary consumers. C) Shrews will have no direct access to matter transferred from tertiary consumers. D) Hawks will have no direct access to nitrogen acquired from the atmosphere.
A
The graph above represents the proportions of hatchlings of certain types of reptiles that are male at different egg incubation temperatures. Which of the following claims is best supported by the data? A) The expression of sex-determination genes in certain reptiles is influenced by temperature. B) Green turtle eggs do not hatch at temperatures above 35°C. C) In reptiles, sex determination is influenced by the sex ratio of the existing population. D) Incubating lizard eggs at constant low temperatures produces a large proportion of males.
A
Which of the following additions to the experimental design will best help test whether the observed habitat preferences were the result of competition between species? A) Placing two individuals from the same population together inside the enclosure B) Introducing different types of plants into the enclosure together with the snakes C) Doubling the number of repetitions for the experimental treatment with T. atratus alone D) Repeating the investigation with an enclosure that is twice as long as the original
A
Which of the following best describes the effect of temperature on corals' ability to produce DMSPDMSP as shown in Figure 1? A) Both juvenile and adult corals produce less DMSPDMSP at 27°C than at 32°C. B) Both juvenile and adult corals produce less DMSPDMSP at 32°C than at 27°C. C) The amount of DMSPDMSP produced over time increases at 32°C in juveniles only. D) The amount of DMSPDMSP produced over time increases at 32°C in adults only.
A
Which of the following best explains the behavior of the guard squirrels? A) The behavior of the guard squirrels increases the survival of close relatives that share the genes of the guard squirrels. B) The guard squirrels confuse the predator, lowering the predator's success rate because the predator cannot tell which squirrel is producing the sound. C) Guard squirrels typically have recessive alleles, and by sacrificing themselves, they lessen the chance that recessive alleles will get passed on. D) Guard squirrels are typically females who have already reproduced, so they are no longer needed by the group.
A
Which of the following best justifies the use of the study area to investigate how one species influences the behavior of another? A) Black stingrays were present in the study area in the presence and absence of blacktip reef sharks. B) Giant shovelnose rays and cowtail rays spent long periods of time at rest while inside the study area. C) Natural barriers in the study area prevented lemon sharks from competing with blacktip reef sharks for limited resources. D) Cowtail rays in the study area formed groups at some stages of the tide cycle but remained alone at other stages.
A
Which of the following conclusions is best supported by the results of the experiment? A) Neither population grows as large when cultured together as each does when cultured separately. B) P. caudatum prefers different food when cultured with P. aurelia than when cultured separately. C) Competition for mates increases when the species are cultured together compared with when they are cultured separately. D) Individuals of the species P. caudatum are smaller when cultured together with P. aurelia than when cultured separately.
A
Which of the following scientific claims about the survival strategies used by organisms in a coral reef ecosystem is best supported by the data presented in Figure 1? A) Smaller members of a vulnerable population are more likely to act collectively. B) Smaller members of a vulnerable population are more likely to rely on defensive coloration. C) Larger members of a vulnerable population are more likely to exhibit aggression. D) Larger members of a vulnerable population are more likely to behave altruistically.
A
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? A) Otters are a keystone species, so their disappearance from the area affected the population size of one other species. B) Otters are a keystone species, so their disappearance from the area resulted in the collapse of an entire community. C) Otters have mutualistic relationships with many other species, so their disappearance from the area affected the population size of another species. D) Otters have mutualistic relationships with many other species, so their disappearance from the area resulted in the collapse of an entire ecosystem.
B
Based on the data in the table, which of the following best describes the habitat preference of T. atratus when introduced alone inside the meshed enclosure? A) T. atratus exhibited equal preferences for all four zones. B) T. atratus exhibited a preference for the zones in or near water. C) T. atratus exhibited a preference for the zones most distant from the water. D) T. atratus exhibited a preference to remain within the zone in which it was initially introduced.
B
Based on the data, which of the following is the best approximation of the rate of growth per week in section IIII from day 14 to day 21 ? A) 3.2g/week B) 4.5g/week C) 5.1g/week D) 9.6g/week
B
Which of the following statements best justifies the use of the experimental results in an investigation of interspecies competition? A) When two populations use different sources of energy, one of the populations will thrive in a shared environment and the other will become extinct. B) When two populations use the same sources of energy, resource availability in a shared environment limits the growth of both populations. C) Because the change in entropy of a system containing two different species is always positive, populations typically grow faster in shared environments. D) Because the free energy of a system containing two different species is always negative, populations that utilize similar resources cannot coexist in nature.
B
Yellow-billed cuckoos typically hatch in midJuly. Emerging cicadas are a primary food source for nesting cuckoos. Which of the following best predicts the effect of wildfires on yellow-billed cuckoo populations? A) The yellow-billed cuckoo population will decline because the decreased ground cover will allow lizards to prey on cuckoo nests. B) The yellow-billed cuckoo population will decline because the cicadas will emerge before the hatching season begins. C) The yellow-billed cuckoo population will grow because the adults will more easily see and eat the cicada nymphs. D) The yellow-billed cuckoo population will remain unchanged because cuckoos do not nest in areas affected by wildfires.
B
Based on the data in the table, which of the following best predicts the results of a study in which natural populations of T. atratus and T. sirtalis are observed together in an environment that includes a freshwater pond? A) Neither T. atratus nor T. sirtalis will be observed near the water. B) T. atratus will be observed near the water whether or not T. sirtalis is present. C) T. sirtalis will be observed near the water whether or not T. atratus is present. D) T. atratus and T. sirtalis will be observed together near the water.
C
Based on the experimental results, which of the following statements best describes the relationship of the two populations that were studied in the investigation? A) The populations have a parasitic relationship in which one species requires the presence of the other to reproduce. B) The populations have a symbiotic relationship in which both species require the presence of the other to reproduce. C) The populations have a competitive relationship in which each species limits the ability of the other to reproduce. D) The populations have a predator/prey relationship in which one species positively influences the ability of the other to reproduce.
C
Based on the information, an increase in the sea slug population would most likely be directly related to which of the following? A) An increase in the eelgrass population B) The introduction of nonnative invertebrates C) A decrease in algae availability D) A decrease in the crab population
D
If the mixed populations were cultured for an additional 25 days, which of the following predictions would be consistent with the data? A) Both populations would stabilize at a small size. B) Both populations would stabilize at a large size. C) Both populations would be eliminated from the culture. D) One population would stabilize at a large size, and the other population would be eliminated from the culture.
D
