Exam 32: An Introduction to Animals

You find a new species of worm and want to classify it.Which of the following lines of evidence would allow you to classify the worm as a nematode and not an annelid?

Which of the following species would you not classify as an animal?

The eye of most vertebrates has a flexible lens which changes shape,by the action of the ciliary muscle,depending on the distance between the lens and the object on which the animal is focusing.Which mollusk's eye is most similar to the vertebrate eye?

Due to its unusual habitat (inside the digestive tracts of other animals),the tapeworm lacks _____.

Figure 32.1 -From the information provided in the figure above,how would you classify the feeding strategy of organism C?

Which of the following would most strongly support your hypothesis that an animal you are observing is an ectoparasite?

While looking at some seawater through your microscope,you spot the egg of an unknown animal.Which of the following tests could you not use to determine whether the developing organism is a protostome or a deuterostome?

Which of the following groups of terms best describes the acoelomorpha?

Why might researchers choose to use molecular data (such as ribosomal RNA sequences)rather than morphological data to study the evolutionary history of animals?

A radula is a specialized feeding organ,used to scrape material off of food for ingestion,much like a cheese grater scrapes shreds off of a block of cheese.Snails,which have this structure,are thus which kind of feeder?

Which of the following is a feature of the tube-within-a-tube body plan in most animals?

The evolution of animal species has been prolific (the estimates go into the millions and tens of millions).To what does the text attribute much of this diversity?

Figure 32.2 -Which morphological trait evolved more than once in animals,according to the phylogeny based on DNA sequence data found in Figure 32.2 above?

Which of the following feeding tactics is consistent with this list of features: Two-part stomach capable of breaking down tough food particles;simple mouthparts;the ability to burrow through,and consume,indigestible fecal material to get to hidden food?

Figure 32.3 Use Figure 32.3 and the following information when answering the next question. In a review paper published in 2000,Adoutte et al.examined some animal phylogenies generated by comparing the ribosomal RNA (rRNA)of animals from many different phyla.They then integrated these independently created phylogenies into one phylogeny that best fit all the data. Figure 32.3 compares a traditional phylogeny based on morphological characteristics (A)to the new molecular-based phylogeny described by Adoutte et al.(B). Note that platyhelminthes,nemerteans,and entoprocts,which do not have coeloms and are classified as acoelomates in the morphological phylogeny,are reclassified as lophotrochozoans in the molecular phylogeny.Similarly,groups classified as pseudocoelomates in the morphological phylogeny are reclassified as either lophotrochozoans or ecdysozoans in the molecular phylogeny;other lophotrochozoans and ecdysozoans have coeloms. -Refer to the paragraph on Adoutte et al.and Figure 32.3.What does this reclassification based on molecular data imply about the evolution of acoelomates,pseudocoelomates,and coelomates?

What do biologists cite as the primary benefit of the evolution of a coelom in animals?

What would you expect to happen if,in the experiment outlined in Figure 32.19,researchers supplied an enzyme that blocked the expression of the Dll gene?

Figure 32.4 -Dll is a gene known to direct limb development in the fruit fly.Researchers studying this gene have found that it is also expressed in developing appendages in animals from many other phyla as well,supporting the hypothesis that all animal appendages may be homologous.However,suppose researchers looking at Dll activity had instead found the results shown in Figure 32.4.What would these results suggest?

Most cnidarians are known to produce toxins.In fact,it has been claimed that one particular species produces the most deadly of all toxins on the planet.What feature of this group most likely evolved simultaneously with the development of these toxins?

Which tissue type,or organ,is not correctly matched with its germ layer tissue?