Which of the following is a difference between food chains and food webs? food webs contain both plants and animals, but food chains contain only plants. food webs separate organisms by trophic level, but food chains do not. food chains show energy flow in an ecosystem, and food webs do not. food chains are linear, while food webs are complex.

What was the land like over 500 million years ago? what was under the sea?

Contrast how pollination is different among gymnosperms and angiosperms.

African penguins, which inhabit the coasts of southern africa, were classified as an endangered species in 2010. two significant threats to their survival are ecosystem damage from oil spills and overfishing by humans. overfishing depletes the food supply of african penguins. the best method to reduce the threat of overfishing would be to . the risk of oil spills could be reduced by increasing the use of , which should oil consumption. if an oil spill does occur, could be used to remove the oil so the ecosystem may more quickly recover.