Problem: Predators play an important role in an ecosystem. For example, if they did not exist, then a single species could become dominant over others. Grazers on a grassland keep grass from growing out of control. Predators can be keystone species . These are species that can have a large effect on the balance of organisms in an ecosystem. For example, if all of the wolves are removed from a population, then the population of deer or rabbits may increase. If there are too many deer, then they may decrease the amount of plants or grasses in the ecosystem. Decreased levels of producers may then have a detrimental effect on the whole ecosystem. In this example, the wolves would be a keystone species. Two teams studied two types of animals: team A studied predators, while team B studied grazers. They learned a lot from this experience. Which team learned that if all of the wolves are removed from a population, then the population of deer or rabbits may increase?

A: team A

Problem: A large log placed in a fire will burn relatively slowly. If the same mass of wood were added to the fire in the form of small twigs, they would burn much more quickly. This is because the twigs provide a greater surface area than the log does. An increase in the surface area of a reactant increases the rate of a reaction. Surface area is larger when a given amount of a solid is present as smaller particles. A powdered reactant has a greater surface area than the same reactant as a solid chunk. In order to increase the surface area of a substance, it may be ground into smaller particles or dissolved into a liquid. In solution, the dissolved particles are separated from each other and will react more quickly with other reactants. Two groups of scientists examined two fires. Group A put a large log on it, and group B made a fire with small twigs. They wanted to see which fire would last longer. Which group had a fire with wood made from smaller particles?

A: group B

Problem: Plants called epiphytes grow on other plants. They obtain moisture from the air and make food by photosynthesis. Most epiphytes are ferns or orchids that live in tropical or temperate rainforests (see Figure below ). Host trees provide support, allowing epiphyte plants to obtain air and sunlight high above the forest floor. Being elevated above the ground lets epiphytes get out of the shadows on the forest floor so they can get enough sunlight for photosynthesis. Being elevated may also reduce the risk of being eaten by herbivores and increase the chance of pollination by wind. Hawk and Brunt were two colleagues studying about plants. Later on, Hawk got specialized in normal plants, while Brunt decided to learn more about epiphytes. Which colleague studied less about plants that grow on other plants?

A: Hawk

Problem: Nearsightedness, or myopia, is the condition in which nearby objects are seen clearly, but distant objects appear blurry. The Figure below shows how it occurs. The eyeball is longer (from front to back) than normal. This causes images to be focused in front of the retina instead of on the retina. Myopia can be corrected with concave lenses. The lenses focus images farther back in the eye, so they fall on the retina instead of in front of it. Two siblings went to the eye doctor, they needed eyeglasses. As it turned out, Ann had myopia, and Jane had farsightedness. They both bought eyeglasses. Which sister had her vision corrected with concave lenses?

A:
Ann