In the phosphorus cycle, phosphorus can recycle through waste products, decomposition, and of terrestrial and aquatic ecosystems.
food chains
the atmosphere
assimilation

Which of the following occurs most often in a population when genetic variation and overproduction are present? some organisms have a lower reproductive success than others. some organisms have a higher reproductive success than others. some organisms have no reproductive success. some organisms do not have genetic variation.

Identify the terms using the following picture. principle of dominance item 1 can be described as the . item 2 can be described as the . the "p" represents from one parent.

Explain how paleontologists use trilobite fossils as index fossils for various geologic time periods.