Which of the following hypotheses is testable using scientific methods?

In an effort to increase milk production of dairy cows, a farmer decides to experiment with a new food additive. Half of the cows (Group 1) are given the new food additive, while half of the cows (Group 2) are not given the food additive. Group 1 represents the ________ group of this experiment, while Group 2 represents the ____ group of the experiment.

Ideally, an experiment studying the effect of a cold medicine should have

What level of ecology is concerned with groups of individuals of different species?

What is a population?

Please read the following scenario to answer the following question(s). Michigan's Isle Royale is located in Lake Superior and is 45 miles long and 9 miles wide. Ecologists estimate that the moose population has been on the island since around 1900. The wolf population, on the other hand, has only been there since the winter of 1949. The conditions had to be just right for the lake to freeze and the weather to be calm enough for the first wolves to make the passage over to the island. When the wolves arrived, they were greeted with a large moose population that had no predators. The moose population was at a dangerously high level, but was kept in check by the arrival of the wolves. This "harmonious" pattern continued for at least 20 years. In 1982, the wolf population suddenly crashed. The problem was a new canine virus. This virus surfaced around the world in 1978 and spread rapidly in about six months. Infected animals can survive, but they have to be treated immediately. Ecologists hypothesized that the virus arrived on the island carried on the shoe of a human traveler. The wolf population decreased from 50 to 14 individuals in a year. While the wolf population dropped, the moose population increased. However, the winter of 1996 was extremely harsh and the moose population experienced a major crash. More than 500 animals died during the winter months, reducing the population to less than 800 animals. The harsh winter that led to the death of many moose in 1996 is an example of a(n) ______.

With regard to the environment as a whole, when is the worst time to apply pesticide to your lawn?

Organisms at the first trophic level are ______.

In the food chain grass → antelope → human → lion, the human is a(n) ______.

The increase in global temperature that is the greenhouse effect is primarily due to ______.

DDT was once used as a(n) ______.

Which one of the following is likely to result from an increase in global atmospheric temperature of as little as 2°C?

Organic farming is environmentally friendly because

Which of the following creates the least amount of soil erosion?

Energy cannot be recycled.

All communities consist of the same number of species.

Wind power is not a renewable soure of energy because wind directions change too often.

A population can increase in size indefinitely.

More sparse urban settlement patterns may help conserve energy and preserve the environment.

Match the following descriptions to its place in the trophic pyramid: a lion feeding on a zebra

Match the following descriptions to its place in the trophic pyramid: a fungus breaking down a dead tree

Match the following descriptions to its place in the trophic pyramid: a human eating a dinner of broccoli, baked potatoes, and steak

Match the following descriptions to its place in the trophic pyramid: a giraffe feeding on leaves of a tree

Match the following descriptions to its place in the trophic pyramid: a plant producing sugar from carbon dioxide and water, using energy from the sun