Ecologists typically model patterns among trophic levels by drawing pyramids. the general name for these pyramids are ecological or trophic pyramids. one more specific type of pyramid is called the pyramid of biomass. this pyramid shows all the biomass at different trophic levels at one point in time. because this ecosystem has only two trophic levels (algae and catfish), it can be represented with a two-tiered pyramid. what ideas do you have about the structure of the biomass pyramid in this pool based on what you already know?

Recently, crops of vegetables such as lettuce and green onions have been contaminated, while they are still on the farm, with bacteria that cause food poisoning. how will science influence the way the government responds to prevent an increase in food-borne diseases? because science has shown that lettuce and green onions are not nutritionally valuable, the government may pass laws that ban the sale of lettuce and green onions. because science has shown that there is no way to prevent bacterial contamination, the government may pass laws that punish businesses that buy lettuce and green onions. because science has shown that the washing of hands prevent the spread of infectious diseases among people, the government may pass laws that require hand washing by everyone who handles food. because science has shown there are ways to find the source of the contamination, the government may pass laws that require farm practices that reduce the contamination of lettuce and green onions.