AP BIO CB 2024 Ecology Missed Questions

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) Neither population grows as large when cultured together as each does when cultured separately.

Which of the following observations would best support this alternative hypothesis? Responses A Previous dips in plankton abundance coincided with other El Niño events. B Primary consumers also experienced a dip in abundance in early 1998. C After mid-1998, there is no correlation between phytoplankton and zooplankton abundance. D CO2 levels in surface waters increased significantly in this region during 1998.

A) Previous dips in plankton abundance coincided with other El Niño events.

A population of 250 birds inhabit the canopy of a tropical rain forest that has a carrying capacity of 400 birds. What is the maximum population growth rate (rmax) if the population grows to 283 in one year? Responses A 0.12 B 0.13 C 0.35 D 0.39

C) 0.35

😢😢 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 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 ? A) 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. B )The guppy population will likely evolve to consume another food source instead of the mosquito larvae

A) 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.

Bt corn varieties are genetically modified to produce a toxin that specifically kills corn borers, a type of insect that eats and damages corn crops. Insects that are not closely related to corn borers are not affected by the toxin. Figure 1 shows the increasing production of Bt corn varieties and the change in the use of broad-spectrum pesticides that were the primary means of killing corn borers before the invention of Bt corn. A The increased use of Bt corn will result in rapid mutation in corn borers. B The toxin in Bt corn kills only the corn pests, leaving other insects unharmed. C Other insect species will replace corn borers and require additional applications of insecticides. D Since Bt corn is not natural like non-Bt corn, it will not interact with the rest of the environment.

A) The increased use of Bt corn will result in rapid mutation in corn borers.

Bison in Yellowstone National Park have a food-limited carrying capacity that determines how their population grows. If the population grows too large, some bison will either starve or migrate to search for more food. The park is able to support a maximum population of 4,500 bison. Park conservation officials must watch the population and prevent the bison from overpopulating, since they would migrate to nearby farms, causing agricultural damage and creating hazards to drivers. The bison begin to migrate when the population reaches 4,000 because of competition for food. If the current population size of bison is 3,652 and the maximum growth rate of the population is 0.28, calculate the population size after one year and determine whether the park will need to take measures to control the population. Responses A The population will be 3,845 after a year. The bison will not pose a problem until the following year, and

A) The population will be 3,845 after a year. The bison will not pose a problem until the following year, and no conservation action will need to take place.

Based on Figure 1, which of the following is the most likely short-term effect of a decrease in the killer whale population? Responses A) The sea otter and kelp populations will increase, while the sea urchin population will decrease. B) The sea otter and sea urchin populations will increase, while the kelp population will decrease. C) The sea otter population will stay the same, while the sea urchin and kelp populations will increase. D) There will be no change to the sea otter, sea urchin, and kelp populations because another predator species will fill the niche previously occupied by the killer whales.

A) The sea otter and kelp populations will increase, while the sea urchin population will decrease.

In a simple ecosystem, a census of the populations in four successive trophic levels was taken as shown above. If level 1 is composed of photosynthetic autotrophs, then the trophic level with 780 individuals will most likely represent Responses A) primary consumers B)secondary consumers C)tertiary consumers D)decomposers E) producers

A) primary consumers

To refine their model of deep-sea biological communities, the researchers investigated areas of the seafloor that are distant from any active hydrothermal vents. Which of the following is the best interpretation of the observation that some octopus species are only found near active hydrothermal vents? Responses A Octopuses depend indirectly on inorganic compounds in the seawater surrounding hydrothermal vents. B Organisms capable of moving across the seafloor are more difficult to observe than are organisms that are rooted in place. C Genetic bottleneck events in isolated areas of the deep ocean adversely affect some octopus populations but not others. D Biomass in a typical marine food web is expected to be greater in higher trophic levels than in lower trophic levels.

A)Octopuses depend indirectly on inorganic compounds in the seawater surrounding hydrothermal vents.

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? Responses A Effect of varying light levels and coral species B Effect of additional DMSP produced by symbionts and the corals' age C Effect of age and varying light levels D Effect of coral species and additional DMSP produced by symbionts

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

A group of researchers suggest that the concentration of available phosphate in this particular section of the British river does not have a significant impact on which plant species grow. Alternatively, another group of researchers hypothesize that levels of available phosphate do affect which plant species grow at this location. Which of the following observations would best support this alternative hypothesis? Responses A Reforestation efforts in Britain near this section of the river have caused changes in the plant community structure. B Increased fertilizer use near this section of the river has led to increased runoff of phosphates into the river. C Spiked water-milfoil adapted to lower phosphorous conditions has been observed to outcompete fennel-leaved pondweed in this section of the river. D Measured levels of SRP in this section of the river have remained constant over a period of time

B) Increased fertilizer use near this section of the river has led to increased runoff of phosphates into the river.

High concentrations of cadmium in the water negatively affect steelhead trout. In a river community, steelhead trout are part of the trophic structure shown in Figure 1. algae -) larva -) nymph -) trout Figure 1. The trophic structure of a river community 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? Responses 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) There will be a large decrease in the trout population, resulting in an increase in damselfly nymphs.

The human sleep-wake cycle is regulated by melatonin. The synthesis of melatonin is regulated by light exposure (Figure 1). The human body typically develops a sleep-wake rhythm that does not respond quickly to change. 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) Melatonin synthesis will be inhibited, and the person will have difficulty sleeping.

Which of the following conclusions is most consistent with the data shown in Figure 2? Responses A Animals that spend 3-5 days in ARD are more likely to survive periods of food scarcity than are animals that spend 13-15 days inARD. B Animals that spend 30 days in ARD live significantly longer after reintroduction of food than animals that spend only 3 days in ARD. C The number of days an animal spends in ARD does not significantly affect its time of survival after reintroduction of food. D The large standard errors of the means make conclusions from the data impossible.

C) The number of days an animal spends in ARD does not significantly affect its time of survival after reintroduction of food.

The population of Japanese sika deer in central Japan was determined each year from 2005 to 2014. The sika deer population underwent logistic growth starting at 26,000 deer in 2005 and stabilized at 58,000 deer between 2012 and 2014. Based on these data, the rmax was determined to be 0.57. Sika deer benefit from the resources in grasslands more than forests; if deforestation occurred, producing more grasslands in the region, the carrying capacity for sika deer population would increase. What would the population size of sika deer be one year after the carrying capacity increased to 70,000 as a result of deforestation? rmax does not change. C The population would grow to 63,667 deer in a year, and the growth rate would decrease the following year. D The population would remain at 58,000 deer, since it had already stabilized.

C) The population would grow to 63,667 deer in a year, and the growth rate would decrease the following year.

Which of the following hypotheses about the effect of zebra mussels on the Hudson River community is best supported by the data in Figure 1 ? Responses A Shoreline fish have replaced open water fish as top predators in a stable community. B Zebra mussels have integrated into the existing community with little effect on the community stability. C The reduction in primary productivity has resulted in an unstable community that will eventually collapse. D Bacterioplankton have replaced phytoplankton as the energy harvesters in the community.

C) The reduction in primary productivity has resulted in an unstable community that will eventually collapse.

The results for treatment groups Vand VI could suggest which of the following questions about the design of the experiment? Responses A Do the glass beakers prevent light from reaching the test samples? B Is the method used for measuring pH harmful to aquatic organisms? C Is the availability of carbon dioxide a limiting factor in aquatic ecosystems? D Does the aquarium water contain living microorganisms?

D) Does the aquarium water contain living microorganisms?

Which of the following statements is consistent with the data shown in the figures? Responses A Grazing activity in a field decreases the species richness of the field. B Different patterns of energy availability in ecosystems will affect species richness. C Forests that develop a closed canopy with a shaded floor will exhibit increased species richness. D The enclosed plots are more efficient at capturing and distributing energy than the clipped plots.

D) The enclosed plots are more efficient at capturing and distributing energy than the clipped plots.

The graph indicates that the sheep population most likely is Responses A) growing in excess of its carrying capacity, since fluctuations in population size occurred after 1850 B) headed for extinction because of the population explosion about 1930 C) regulated by density-independent factors, because there appears to be about a 10-year cycle of sharp declines in size D) shifting from a K-selected strategy to an r-selected strategy E) stable after 1850 under the effects of density-dependent regulating factors

E) stable after 1850 under the effects of density-dependent regulating factors

Deep ocean floor communities contain very little life. In constant darkness, the water at these depths hovers around 2°C. Superheated water streams out of the vents at temperatures approaching 400°C. Hydrothermal vent zones have a density of organisms 10,000 to 100,000 times greater than found on the surrounding seafloor. they found a total absence of photosynthetic organisms at all vents, identifying mats of bacteria as the producers of the carbon compounds that are used by the rest of the community for growth, repair, and as an energy source. Which of the following describes how the vent bacteria harvest energy to produce organic compounds for use by the vent community? B The bacteria function as chemoautotrophs, extracting energy from hydrogen-rich inorganic molecules. D The bacteria can recycle the energy from the waste products and dead material produced by the heterotrophs of the vent community into energy

b) The bacteria function as chemoautotrophs, extracting energy from hydrogen-rich inorganic molecules.