The diagrams below show a marine food web and an incomplete terrestrial food web. The ogranism in the terrestrial food web that corresponds to kill in the marine food web is labeled X. Which of the following organisms is most likely organism X?

The relationship between fleas and a dog is most similar relationship between...

In the Pacific Ocean, sea birds and large fish eat krill, which are small-shrimp-like crustaceans. As populations of sea birds and large fish increase, how will the ecosystem be affected?

After Jeff read an article describing an experiment, he concluded that the experiment was valid. The reasons he thought the experiment was valid were because it included several trials, and because several other scientists had conducted the same experiment with similar results. Which statement best describes the reason Jeff accepted the results of this experiment?

In an investigation, yeast was grown in a nutrient culture that was maintained at a constant temperature. After a few days, paramecia that feed on yeast were introduced into the culture medium. The numbers of yeast cells and paramecia were determined over a period of several weeks. See the graph.

What might occur if another species of paramecium that feeds on the same species of yeast is introduced into culture?

The cleaner wrasse, a small marine fish, periodically cleans harmful parasites from the mouth and body of the moray eel. The moray, in turn, protects the wrasse from larger predators and provides it with a constant supply of food. This is an example of the type of relationship known as ...

The diagram shown represents a portion of a food web in a Florida ecosystem. What effect would the removal of the cormorant population have on the state of dynamic balance present in the food web?

Scientific advancement depends on discovery and the development of new theories. Which of these statements best describes how replication can affect scientific progress?

In Florida, bluebirds and sparrows inhabit nearly the same ecological niche. In many areas, bluebirds are being replaced by the sparrows as the result of....

In his studies of birds in the Galapagos Islands, Charles Darwin observed that a few bird varieties with similar beak size and shape inhabited a particular area. The limited number of similar varieties was most likely due to...

Mangrove trees are common to the Florida Everglades. The tree roots serve as a place for freshwater oysters to attach when the tide is high, as shown in the picture. The oysters are protected from predators when attached to the roots underwater. The oysters do not harm the trees nor do they provide any benefit to the trees. Which of the following relationships is most similar to the relationship between the mangrove trees and the oysters?

An important need for a bird is a safe place to build a nest. If a bird did not have a place to build a nest, what would most likely occur?

Honeybees are important pollinators of flowers. Mites that live in the bodies of bees can attack honeybee colonies. Some birds, amphibians, and insectes eat honeybees. Which of the following relationships is not included in the description above?

Eva is investigating the germination of bean seeds. She plants 30 bean seeds each in three in identical 25-cm-by-25-cm square containers and plans to give the same amount of sunlight and water to each container. She will place each container in a different room, with each room at a different temperature. A variable that is purposely changed to test a hypothesis is a(n)..