In 1969, two scientists devised an experiment to test a hypothesis that the number of species in an ecosystem depends on the area of the ecosystem. They counted all the arthropod species on a few very tiny islands. They then exterminated all the arthropods (mostly insects) with a pesticide. Over six months, they monitored the gradual repopulation of the island and noticed that by the end of the observation period, each island had almost the same number of species as it had before pesticide was used. However, the kinds of species that arrived often differed from the species that were on the island prior to pesticide use. Here is a chart that illustrates the results.Based on the chart, which trophic level suffered the greatest net loss (number of species) in diversity?
A science student hypothesized that the rate of evaporation of water depends on the shape of the container the water is placed in. She decided to measure the amount of water evaporated when 300 ml of water in five different containers was heated from room temperature to 90 C on preheated hot plates. She used five cylindrical 500-milliliter glass containers, each having the same wall thickness but a different base radius and height. In other words, some containers were narrow and tall, others were wide and shallow. The following table lists the dimensions of the containers and the amount of water initially present.She placed each container, containing the same amount of water, on a hot plate, and placed a thermometer in each to monitor the temperature. She noticed that the temperature was increasing aster in the containers with a larger radius. After some time, the temperature in the 10-cm radius container reached the set 90 C.Following container 5, the water in containers 4, 3, 2, and 1, in that order, reached the set temperature. The student checked the volume of the water in each container and found that it was lower than 300 ml. She also found that the decrease in volume was highest in the container with the largest radius. In container 1, volume decrease was barely detectable.What can the student conclude from the data?
Which two statements are valid objections to the experimental setup?a. All the containers were filled with the same amount of water. b. A different hot plate was used to heat water in different containers. c. Water in different containers was heated for different amounts of time. d. The containers were not filled completely.
The following graph shows how the concentration (amount per unit volume) changes with time. What information can be obtained from the data?
Is Pluto a Planet? Based on perturbations in Neptunes orbit, the search for a ninth planet was conducted and Pluto was discovered in 1930. Pluto orbits the sun just like the other eight planets, and it has a moon, Charon, and a stable orbit. Based on its distance from the sun, Pluto should be grouped ith he planets known as gas giants. In addition, Pluto, like the planet Mercury, has little or no atmosphere. Pluto is definitely not a comet because it does not have a tail like a comet when it is near the sun. Pluto is also not an asteroid, although its density is closer to an asteroid than to any of the other planets. Pluto is a planet because it has been classified as one for more than sixty years since its discovery.Which argument supporting the classification of Pluto as a planet is the weakest?
Is Pluto a Planet? Based on perturbations in Neptunes orbit, the search for a ninth planet was conducted and Pluto was discovered in 1930. Pluto orbits the sun just like the other eight planets, and it has a moon, Charon, and a stable orbit. Based on its distance from the sun, Pluto should be grouped ith he planets known as gas giants. In addition, Pluto, like the planet Mercury, has little or no atmosphere. Pluto is definitely not a comet because it does not have a tail like a comet when it is near the sun. Pluto is also not an asteroid, although its density is closer to an asteroid than to any of the other planets. Pluto is a planet because it has been classified as one for more than sixty years since its discovery.Which one of the following statements is NOT backed with an explanation?
