| Most bivalves have photosynthetic endosymbionts in the visceralmass. 8.If a marine biology student discovered a dorsoventrallyflattened marine worm, what would be an effective way to determineif the specimen was a flatworm or a ribbon worm? | Examine the morphology of theexcretory system. | | Look for a head at the anteriorend. | | Determine the number of embryonicmembranes. | | Look for an anus. 9.Inside its beak an octopus has a rasping tongue that is usedto tear apart food, which gastropod structure is this analogousto? | Nephridium | | Radula | | Shell | | Mantle 10.Pinworm is spread by contact, and the worms cause severeitching around the anus. Why is it so common? | Insect vectors spread thedisease. | | The intense itch produces anintense desire to scratch. | | The eggs end up in the soil. | | Sometime people don't wash their hands after scratching theirperi-anal region. 11.Why would a leech have a hard time feeding if it did notproduce anticoagulants? | The blood would stop flowing aftera short time. | | The leech would have a hard timeremaining attached to its host. | | The leech would have a hard timelocating appropriate hosts. | | The pain of the leech bite would cause the leech to bedetected. 12.The scolex of a tapeworm contains the mouth and the anteriorneural ganglia. | True | | False
13.In what way are a human and a crab similar? | Both have a continuos growthpattern. | | Both have closed circulatorysystems. | | Vertebrates and arthropods aredeuterostomes. | | Both have muscles that pull against rigid skeletons. 14.What is a simple way for determining if an annelids is apolychaete or a clitellate? | The amount of setae | | Possession of a closed circulatorysystem | | The layout of the digestivesystem | | The number of segments 15.At a celebratory dinner for a recent publication, a marinebiologist ordered the lobster claw appetizer. What part did sheorder? | Telson | | Uropods | | Nauplius | | Cheliped 16.Humans have directdevelopment, a closed circulatory system, well-developed eyes, andlarge brains. Which mollusk also shares these features? | Octopus | | Slug | | Chiton | | Nudibranch | | | | | | | | | |