Blog

Two communities each contain the same number of species. In one community, the major species are all present in approximately equal percentages. In the other, one species makes up more than 70 percent of the species, while all the others are divided among the remaining 30 percent. The two communities differ in their species _______.

 During fall and winter in the temperate zone of the Northern Hemisphere, photosynthesis slows to a stop, and CO2 remains in the atmosphere. In spring and summer, photosynthesis increases and pulls CO2 out of the atmosphere, decreasing the size of the CO2 _______ and increasing the _______ of CO2 into and out of the compartment.

Before the Industrial Revolution, the concentration of CO2 in Earth’s atmosphere was 265 parts per million (ppm). At the end of 2012, the concentration was 393 parts per million. Given the correlation of atmospheric CO2 concentration with global temperature rise, what does this change suggest about the global carbon budget?

The number of individuals in a population divided by the area that the population takes up is known as the _______ of the population.

Please use the following information to answer the two questions below.    In this experiment, Balanus was removed from the habitat shown on the left.

Based on what you have read about metapopulation dynamics in Edith’s checkerspot butterflies, which statement is most likely to be true?

Suppose that Earth’s tilt suddenly shifted, such that it was still tilted in the same direction but at a 26° angle instead of a 23° angle.  Which event would most likely result from such a change in Earth’s tilt?

Suppose that Earth’s tilt suddenly shifted, such that it was still tilted in the same direction but at a 26° angle instead of a 23° angle.  Which event would most likely result from such a change in Earth’s tilt?

What is the best and most complete description of the relationship between various biogeochemical cycles on Earth, as we currently understand these cycles?

The rate of nitrogen recycling is slowest when the nitrogen is located in which global pool?