12. Which of the following is NOT a correct statement about food chains?
a)the food-chain concept is helpful
in thinking about community interactions, but is an oversimplification of the actual interactions
b)food webs show the relationships among muiple food chains
c)food webs are better than food chains for showing the position of omnivores with the community
d)food chains are often complex and intertwined
e)all of the above are correct statements about food chains
13.Which of the following is an example of a mutualistic integration between species?
a)a large fish visits a cleaner fish that removes parasites by eating them off the affected areas
b)bees get a food resource by visiting flowers, and flowers get pollinated by bee activites
c)a bird makes a nest in a thorny tre, where it benefits from extra protection from predators
d)a and b
14. Which of the following ecosystems would NOT be affected by a decrease in bee populations?
e)all of the above would be affected by a decrease in bee populations