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Which of the following is NOT one of the ways an individual organism can respond to external environmental changes?

A biologist spent many years researching the rate of evolutionary change in the finch populations of a group of islands. It was determined that the average beak size (both length and mass) of finches in a certain population increased dramatically during an intense drought between 1981 and 1987. During the drought, there was a reduction in the number of plants producing thin-walled seeds. Which of the following procedures was most likely followed to determine the change in beak size?

Which of the following statements best explains the structure and importance of plasmids to prokaryotes?

The left side of the table is labeled First Base in Codon, and labels the main rows, from top to bottom, U, C, A, G. The top side of the table is labeled Second Base in Codon, and labels the main columns, from left to right, U, C, A, G. The right side of the table is labeled, Third Base in Codon, and labels each of the main rows U C A G.The data in the table reads as follows: First Base U and Second Base U with Third Base U, results in U U U phenylalanine; with Third Base C results in U U C phenylalanine; with Third Base A, results in U U A leucine, and with Third Base G, results in U U G leucine. First Base C and Second Base U with Third Base U, results in C U U leucine; with Third Base C, results in C U C leucine; with: Third Base A, results in C U A leucine, and with Third Base G, results in C U A leucine. First Base A and Second Base U with Third Base U, results in A U U isoleucine; with Third Base C, results in A U C isoleucine; with Third Base A, results in A U A isoleucine; and with Third Base G, results in A U G methionine or start. First Base G and Second Base U with Third Base U, results in G U U valine; with Third Base C, results in G U C valine; with Third Base A, results in G U A valine, with Third Base G, results in G U G valine. First Base U and Second Base C with Third Base U, results in U C U serine; with Third Base C, results in U C C serine; with Third Base A, results in U C A serine; and with Third Base G, results in U C G serine. First Base C and Second Base C with Third Base U, results in C C U proline; with Third Base C, results in C C C proline; with Third Base A, results in C C A proline; and with Third Base G, results in C C G proline. First Base A and Second Base C with Third Base U, results in A C U threonine; with Third Base C, results in A C C threonine; with Third Base A, results in A C A threonine; and with Third Base G, results in A C G threonine. First Base G and Second Base C with Third Base U, results in G C U alanine; with Third Base C, results in G C C alanine; with Third Base A, results in G C A alanine; and with Third Base G, results in G C G alanine. First Base U and Second Base A with Third Base U, results in U A U tyrosine; with Third Base C, results in U A C tyrosine; with Third Base A, results in U A A stop; and with Third Base G, results in U A G stop. First Base C and Second Base A with Third Base U, results in C A U histidine; with Third Base C, results in C A C histidine; with Third Base A, results in C A A glutamine; and with Third Base G, results in C A G glutamine. First Base A and Second Base A with Third Base U, results in A A U asparagine; with Third Base C, results in A A C asparagine; with Third Base A, results in A A A lysine; and with Third Base G, results in A A G lysine. First Base G and Second Base A with Third Base U, results in G A U aspartate; with Third Base C, results in G A C aspartate; with Third Base A, results in G A A glutamate; and with Third Base G, results in GAG glutamate. First Base U and Second Base G with Third Base U, results in U G U cysteine; with Third Base C, results in U G C cysteine; with Third Base A, results in U G A stop; and with Third Base G, results in U G G tryptophan. First Base C and Second Base G with Third Base U, results in C G U arginine; with Third Base C, results in C G C arginine; with Third Base A, results in C G A arginine; and with Third Base G, results in C G G arginine. First Base A and Second Base G with Third Base U, results in A G U serine; with Third Base C, results in A G C serine; with Third Base A, results in A G A arginine; and with Third Base G, results in A G G arginine. First Base G and Second Base G with Third Base U, results in G G U glycine; with Third Base C, results in G G C glycine; with Third Base A, results in G G A glycine; and with Third Base G, results in G G G glycine. 5′- GTT TGT CTG TGG TAC CAC GTG GAC TGA – 3′ The DNA sequence is a small part of the coding (nontemplate) strand from the open reading frame of β-hemoglobin gene. Given the codon chart, what would be the effect of a mutation that deletes the G at the beginning of the DNA sequence?

There is a key of plants below the time progression, containing grasses, annual plants, shrubs, oak trees and other trees. In the first time point the grass covers the ground and there are a few annual plants. The second time point has fewer grasses, 2 shrubs, and 3 oak trees. The third time point has no grass, 2 shrubs, 2 oak trees that have grown taller, and 3 other trees. The fourth time point has one oak tree that has grown even taller, and three other trees that have grown taller. There are no grasses, annual plants, nor shrubs. The fifth and final time point has one large oak tree and two large other trees.There are no grasses, annual plants, nor shrubs. The diagram above shows the progression of ecological events after a fire in a particular ecosystem. Based on the diagram, which of the following best explains why the oak trees are later replaced by other trees?

In an experiment to determine the effect of light availability on species richness in an environment, a grassland was divided into 26 plots that were assigned to one of two treatment groups: 1. Clipped – plots were mowed to simulate the grazing of herbivores that maintain the low height of grasses. 2. Enclosure – plots were enclosed in fences, and grasses were allowed to grow undisturbed to their maximum height. After eight years, data was collected on the amount of light penetration to the soil (bottom light density) and the number of species in the two treatment groups. Figure 1 shows the averaged light penetration measurements, and Figure 2 shows the averaged number of species per plot type. The horizontal axis is labeled Treatment, and the two bars indicated along it are labeled Enclosed and Clipped respectively. An error range is given for each bar. The vertical axis is labeled Bottom Light Density, in watts per meter squared, and the numbers 0 through 600, in increments of 200, are indicated. Each bar is described as follows. Note that all values are approximate. Enclosed. 500, plus or minus 25. Clipped. 170, plus or minus 25. Figure 1. Average bottom light intensity in clipped plots versus enclosed plots The horizontal axis is labeled Treatment, and the two bars indicated along it are labeled Enclosed and Clipped respectively. An error range is given for each bar. The vertical axis is labeled Average Number of Species per Plot, and the numbers 0 through 20, in increments of 2, are indicated. Each bar is described as follows. Note that all values are approximate. Enclosed. 11.6, plus or minus 0.3. Clipped. 17, plus or minus 1. Figure 2. Richness comparison of two treatments Which of the following statements is consistent with the data shown in the figures?

Why would a community in the early stages of secondary succession be less productive than a community in the later stages of secondary succession?

A colony of termites was exposed to an atmosphere of 100 percent oxygen for three days. The insects were not immediately harmed by the treatment, but the protozoa that lived in the termites’ guts were eliminated. The treated termites continued to behave normally and to eat wood, but they began to starve after a short time. When the treated termites were instead fed wood contaminated with the feces of untreated termites, the treated termites regained the ability to digest wood and no longer starved. The best analysis of the results of the experiment is that

_______ is the process in which a protein is assembled at a ribosome.

In the American Southwest, annually emerging cicadas are dependent upon the cottonwood trees in the floodplain. Adult male cicadas perch in the cottonwood trees and chirp to attract females. Females lay their eggs in the branches of the cottonwoods, and, upon hatching, the cicada nymphs drop to the ground, burrow into the soil, feed on the tree roots, and later emerge as adults. Other organisms in the floodplain community prey on the cicadas, as shown in the food web. Arrows extend from the cicada to a yellow billed cuckoo, a sparrow, a lizard, a wasp, a black widow, and a kestrel. An arrow extends from a cottonwood to the cicada. An arrow extends from a lizard to a kestrel. An arrow extends from a sparrow to a kestrel. An arrow extends from a yellow billed cuckoo to a kestrel. Figure 1. Food web in floodplain community Human activity has caused a decrease in the amount of flooding and an increase in the incidence of wildfires in the floodplain. In an investigation into the recent changes in the floodplain ecosystem, researchers monitored the soil temperature, amount of cottonwood ground coverage (i.e., area of the ground that is shaded by leaves), and cicada emergence for a period from mid-June until late July. The results of the investigation are represented in Figure 2 and Figure 3. The horizontal axis is labeled “Cottonwood Ground Coverage, in percent,” and the numbers O through 100, in increments of 20, are indicated. The vertical axis is labelled “Mean June Soil Temperature, in degrees Celsius,” and the numbers 18 through 28, in increments of 2, are indicated. The line of best fit is shown. The line begins at the point with coordinates 2 percent of cottonwood ground coverage comma 25 degrees Celsius and moves directly downward and to the right ending at the point with coordinates go percent cottonwood ground coverage and 19 degrees Celsius. Figure 2. Effect of cottonwood ground coverage on soil temperature The horizontal axis is labeled “Mean June Soil Temperature, in degrees Celsius,’ and the numbers 18 through 28, in increments of 2, are indicated. The vertical axis is labeled “Mean Emergence Date,’ and the dates 6 13 through 7 23, in increments of 5 days, are indicated. The line of best fit is shown. The line begins at the point with coordinates 19 degrees Celsius comma the date 7 21 and moves directly downward and to the right ending at the point with coordinates 26 point 5 degrees Celsius comma the date 6 13. Figure 3. Relationship between soil temperature and cicada emergence date To assess the impact of wildfires on soil temperature and cicada emergence, the researchers compared mean emergence dates for two natural sites where portions had been affected by wildfire. In addition, cicada emergence was monitored at an experimental site where the soil temperature was experimentally maintained. The data are shown in the table. MEAN CICADA EMERGENCE DATES AT SITES AFFECTED BY WILDFIRES OR WITH EXPERIMENTALLY CONTROLLED SOIL TEMPERATURE The table shows Mean cicada emergency dates for Natural Site 1, Natural Site 2, and Experimental Site. For Natural Site 1, the Mean Emergency Date for Unburned is July 8, and for Burned is June 18. For Natural Site 2, the Mean Emergency Date for Unburned is July 15, and for Burned is July 3. For Experimental Site, the Mean Emergency Date for 24 degree Celsius is July 14, and for 27 degree Celsius is July 5. Based upon the data, which of the following best describes the effect on the timing of cicada emergence if the cottonwood ground cover decreases from 50 percent to 25 percent?