Explain how the specific immune response differs between two patients who have been infected with the same virus. patient a was previously vaccinated against the virus, while patient b has no previous exposure to the virus.

One statements is an example of a scientific observation. another statement is an example of a scientific explanation. identify the correct statement for each category to illustrate how scientific explanations are inferred from scientific observations.

An ecologist is studying the effects that a population of predators is having on a population of a prey. he used data from the field to produce this graph. which conclusion can draw from the graph?

This is a typical grassland food web. it is also a small picture of an important cycle on earth: the carbon cycle. describe how the carbon gets into this food web. a) bacteria and fungi, the decomposers, recycle carbon from dead organisms. b) carbon is found in the grass and is passed from one level to the next in this food web. eliminate c) all living things give off carbon dioxide as a by-product of respiration and it is released into the atmosphere. d) plants use carbon dioxide as a reactant in photosynthesis, to make usable chemical energy in the form of a sugar.