As dense populations of oysters filter phytoplankton from the water column in bays and estuaries, the water becomes increasingly murky and the visibility goes to zero.

Questions 36-38: Multiple choice The experience of a phytoplanktonic organism with a low Reynold’s number swimming through water could be compared to the feeling of a human:

The organisms associated with hydrothermal vents do not require oxygen.

higher productivity (per square meter)      

constitute an important food for super charismatic predators that need to consume large amounts of food to help them keep warm 

Questions 10-13: A 2001 paper by J. Jackson and 18 other authors made the provocative suggestion that progressive loss of large consumers, due to human consumption beginning long ago, underlies the present nearly collapsed state of important coastal ecosystems.  For each of these ecosystems what are these historically important key consumers that now have relatively small populations in many places?  kelp forests  

 Low biomass of algae on a coral reef that is teeming with large schools of  herbivorous fishes is a reliable indicator that there is negligible production of new algal  biomass, and the herbivores must be foraging for worms and bivalves instead.   

storing food in the form of lipids rather than carbohydrates

consume fast-growing algae that would otherwise overgrow the dominant structure-producing organisms

seagrass meadows