A 20 kg block rests on a rough horizontal table.

Afood web shows who eats who in any given habitat. every living thing, from one-celled algae to giant blue whales, needs food to survive. each food web is a possible pathway that energy and matter can follow through the habitat. a food web begins with producers: organisms that convert sunlight into usable chemical energy. the food web is completed by the decomposers who turn organic wastes, such as decaying plants, into inorganic materials, such as nutrient-rich soil. decomposers complete the cycle of life, returning nutrients to the soil or oceans for use by producers. in this food web, identify the decomposer.

The graph shows a trend in an ecosystem over time caused by increased pollution in the region. what can you conclude from the graph? a. there’s lower biodiversity among birds. b. there’s a higher reproductive rate among birds. c. there’s a significant decline in the number of producers. d. other types of animals were unaffected by pollution.

Which specimen would best be viewed using a compound light microscope?