Exam 31: Protostome Animals

The presence of a lophophore in a newly discovered species would suggest that the species ________.

The body cavity type for arthropods and mollusks can best be described as ________.

Nematodes and arthropods both ________.

Which mollusk group can be described as having several calcium carbonate plates along their dorsal side?

Use the following information to answer the question(s) below. Nudibranchs, a type of predatory sea slug, can have various protuberances (that is, extensions) on their dorsal surfaces. Rhinophores are paired structures, located close to the head, which bear many chemoreceptors. Dorsal plummules, usually located posteriorly, perform respiratory gas exchange. Cerata usually cover much of the dorsal surface and contain nematocysts at their tips. -The antennae of insects have a function most similar to that of ________.

Which of the following are characteristics of arthropods? 1) protostome development 2) bilateral symmetry 3) a pseudocoelom 4) three embryonic germ layers 5) a closed circulatory system

A terrestrial mollusk without a shell belongs to which clade?

What would be the best anatomical feature to look for to distinguish a gastropod from a chiton?

Refer to the accompanying figure. Suppose new molecular analyses indicated that the phylum Annelida had diverged from the arthropod lineage after Onychophora and Tardigrada. What would this imply about protostome evolution? 1) Segmentation evolved only once within protostomes. 2) The annelid lineage gained and then lost the ability to molt. 3) The annelid lineage gained and then lost jointed limbs.

Whiteflies are common pest insects found on cotton, tomato, poinsettia, and many other plants. Nymphs are translucent and mostly sessile, feeding on their host plants' phloem (sap) from the undersides of leaves. They undergo incomplete metamorphosis into winged adults. Because whitefly nymphs cannot escape predation by moving, you hypothesize that their translucent bodies make them hard to spot by predators. How could you directly test this hypothesis?

Use the following information to answer the question(s) below. Many terrestrial arthropods exchange gases with their environments by using tracheae, tubes that lead from openings (called spiracles) in the animal's exoskeleton or cuticle directly to the animal's tissues. Some arthropods can control whether their spiracles are open or closed; opening the spiracles allows carbon dioxide produced in the tissues to travel down the tracheae and be released outside the animal. Klok et al. measured the carbon dioxide emitted over time (represented by VCO2) by several species of centipedes. The figure below presents graphs of their results for two species, Cormocephalus morsitans and Scutigerina weberi. (C. J. Klok, R. D. Mercer, and S. L. Chown. 2002. Discontinuous gas-exchange in centipedes and its convergent evolution in tracheated arthropods. Journal of Experimental Biology 205:1019-29.) Copyright 2002 The Company of Biologists and the Journal of Experimental Biology. -What would be the most direct effect of removing or damaging an insect's antennae? The insect would have trouble ________.

Arthropod exoskeletons and mollusk shells both ________.

Which adaptation is unique to insects among all protostomes?

The heartworms that can accumulate within the hearts of dogs and other mammals have a pseudocoelom, an alimentary canal, and an outer covering that is occasionally shed. To which phylum does the heartworm belong?

Among protostomes, which morphological trait has shown the most variation?

Use the following information to answer the question(s) below. A farm pond, usually dry during winter, has plenty of water and aquatic pond life during the summer. One summer, Sarah returns to the family farm from college. Observing the pond, she is fascinated by some six-legged organisms that can crawl about on submerged surfaces or, when disturbed, seemingly "jet" through the water. Watching further, she is able to conclude that the "mystery organisms" are ambush predators, and their prey includes everything from insects to small fish and tadpoles. -Sarah noticed the presence of many empty exoskeletons attached to emergent vegetation. These exoskeletons looked exactly like those of the largest of the "mystery organisms" she had seen in the pond. They also looked similar to the bodies of the dragonflies that patrolled the surface of the pond. If Sarah had learned a lot from her college biology class, what should she have concluded about the mysterious pond organisms?

Which one of the following is a lophotrochozoan?

You find a multilegged animal in your garden and want to determine if it is a centipede or a millipede. You take the animal to a university where a myriapodologist quickly tells you that you have found a centipede. Which of the following may have allowed her to make this distinction?

Use the following information to answer the question(s) below. Nudibranchs, a type of predatory sea slug, can have various protuberances (that is, extensions) on their dorsal surfaces. Rhinophores are paired structures, located close to the head, which bear many chemoreceptors. Dorsal plummules, usually located posteriorly, perform respiratory gas exchange. Cerata usually cover much of the dorsal surface and contain nematocysts at their tips. -The spiracles and tracheae of insects have a function most similar to that of ________.

A(n) ________ has a crown of ciliated tentacles that function in feeding.