Mastering Biology Chapter 33

How many of the following are characteristics of at least some members of the phylum Cnidaria? 1. a gastrovascular cavity 2. a polyp stage 3. a medusa stage 4. cnidocytes 5. a pseudocoelom

Which of the following is true of members of the phylum Cnidaria? They are not capable of locomotion because they lack true muscle tissue. They are primarily filter feeders. They may use a gastrovascular cavity as a hydrostatic skeleton. They have either, or both, of two body forms: mobile polyps and sessile medusae. They are the simplest organisms with a complete alimentary canal (two openings).

The members of which clade in the phylum Cnidaria occur only as polyps?

Which clade in the phylum Cnidaria includes "jellies" with rounded (as opposed to boxlike) medusae? Anthozoa Scyphozoa Cubozoa Hydrozoa

Which characteristic(s) is (are) shared by both cnidarians and flatworms? a digestive system with a single opening true muscle dorsoventrally flattened bodies radial symmetry two of these

A stalked, sessile marine organism has several feathery feeding structures surrounding an opening through which food enters. The organism could potentially be a cnidarian, a lophophorate, a tube-dwelling worm, a crustacean, or an echinoderm. Which of the following traits, if found in this organism, would allow the greatest certainty of identification? the presence of what seems to be radial symmetry a nervous system a water vascular system a hard covering made partly of calcium carbonate a digestive system with mouth and anus separate from each other

Which of the following animal groups is entirely aquatic? Nematoda Crustacea Echinodermata Mollusca Platyhelminthes

Which of the following is a diploblastic phylum of aquatic predators? Mollusca Arthropoda Annelida Echinodermata Cnidaria

Ectoprocts and brachiopods are collectively referred to as _____. trochophorates lophophorates eumetazoans ecdysozoans flatworms

The excretory organs of annelids are protonephridia. flame bulbs. malpighian tubules. metanephridia. skin gills.

The larvae of many common tapeworm species that infect humans are usually found crawling in the abdominal blood vessels of cows and pigs. encysted in freshwater snails. encysted in the muscles of an animal, such as a cow or pig. crawling in the intestines of cows and pigs.

While sampling marine plankton in a lab, a student encounters large numbers of fertilized eggs. The student rears some of the eggs in the laboratory for further study and finds that the blastopore becomes the mouth. The embryo develops into a trochophore larva and eventually has a true coelom. These eggs probably belonged to a(n) echinoderm. nematode. mollusc. arthropod. chordate.

A brachiopod can be distinguished from a bivalve by the presence of a distinct head. suspension feeding. a lophophore. two hinged shells. a digestive system with separate mouth and anus

Which mollusc clade includes members that undergo embryonic torsion? chitons gastropods cephalopods bivalves

A terrestrial mollusc without a shell belongs to which clade? bivalves cephalopods chitons gastropods

A radula is present in members of which clade(s)? bivalves and chitons bivalves bivalves, gastropods and chitons bivalves, gastropods and cephalopods chitons, gastropods and cephalopods

If nudibranch rhinophores are located at the anteriors of these sea slugs, then they contribute to the sea slugs' identity as lophotrochozoans. segmentation. lack of torsion. cephalization. ability to successfully carry out a sessile lifestyle

What structure is responsible for gas exchange in most spiders? book lungs chelicerae Malpighian tubules tracheal tubes the pedipalp

Which of the following is a characteristic of nematodes? They have only longitudinal muscles. They have a true coelom. Many species are diploblastic. They have a gastrovascular cavity. All species can be characterized as scavengers.

How many of the following can be used to distinguish a nematode worm from an annelid worm? 1. type of body cavity 2. number of muscle layers in the body wall 3. presence of segmentation 4. number of embryonic tissue layers 5. shape of worm in cross-sectional view 1 2 and 3 1, 2, and 3 2, 3, 4 and 5 All of the options are correct.

Nematode worms and annelid worms share which of the following features? absence of species with parasitic lifestyles use of fluid in the body cavity as a hydrostatic skeleton presence of segmentation ecdysis presence of a circulatory system

A student observes a wormlike organism crawling about on dead organic matter. Later, the organism sheds its outer covering. One possibility is that the organism is a larval insect (like a maggot). However, it might be a member of the phylum ________, and one way to distinguish between the two possibilities is by looking for the presence or absence of ________. Nematoda; an alimentary canal Annelida; a body cavity Annelida; muscle in the body wall Platyhelminthes; a cuticle of chitin Nematoda; a circulatory system

How many 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 1 1 and 2 1, 2, and 4 2, 3, 4, 5 All of the options are correct.

Among the invertebrate phyla, phylum Arthropoda is unique in possessing members that have segmented bodies. a cuticle. a ventral nerve cord. wings. open circulation.

You find a small animal with eight legs crawling up your bedroom wall. Closer examination will probably reveal that this animal has a head, thorax, and abdomen. simple, but not compound, eyes. tracheae and spiracles. two pairs of antennae.

What distinguishes complete metamorphosis from incomplete metamorphosis in insects? the radically different appearance between adults and earlier life stages the presence of wings in the adult, but not in earlier life stages the presence of sex organs in the adult, but not in earlier life stages Three of these responses are correct. Two of these responses are correct.

The possession of two pairs of antennae is a characteristic of crustaceans. insects. spiders. millipedes. centipedes.

Which of the following describe(s) echinoderms? Tubefeet provide motility in most species. Digestion occurs completely outside of the organism. They are found in both freshwater and saltwater environments. They have an exoskeleton of hard calcareous plates. Hemolymph circulates in the water vascular system.

A land snail, a clam, and an octopus all share gills. a mantle. a radula. embryonic torsion. distinct cephalization.

Which phylum is characterized by animals that have a segmented body? Porifera Mollusca Arthropoda Platyhelminthes Cnidaria

The water vascular system of echinoderms moves water through the animal's body during suspension feeding. is bilateral in organization, even though the adult animal is not bilaterally symmetrical. functions in locomotion and feeding. is analogous to the gastrovascular cavity of flatworms. functions as a circulatory system that distributes nutrients to body cells

In Figure 33.2 in your textbook, which two main clades branch from the most recent common ancestor of the eumetazoans? Rotifera and Deuterostomia Deuterostomia and Bilateria Porifera and Cnidaria Lophotrochozoa and Ecdysozoa Cnidaria and Bilateria

Which of the following is true of annelids? They perform gas exchange across their skin. They have pseudocoeloms. They have an open circulatory system. They have a gastrovascular cavity. They have a nerve net.

A marine biologist dredges up a small animal from the bottom of the ocean. It is uniformly segmented, with short, stiff appendages and soft, flexible skin. It has a complete digestive system and a closed circulatory system, plus multiple true coeloms. Based on this, you determine that the animal must be a(n) _____. A marine biologist dredges up a small animal from the bottom of the ocean. It is uniformly segmented, with short, stiff appendages and soft, flexible skin. It has a complete digestive system and a closed circulatory system, plus multiple true coeloms. Based on this, you determine that the animal must be a(n) _____. lancelet annelid mollusc crustacean roundworm

Nematodes and arthropods are the largest ecdysozoan phyla. Which of the following statements are true? Select all that apply. Select all that apply. Both nematodes and arthropods possess an external covering, or cuticle. The cuticle in nematodes lengthens as the animal grows. Nematodes are acoelomate, whereas arthropods are coelomate. Arthropods possess an open circulatory system. Some nematodes are parasitic on humans. Arthropods are named for their jointed appendages. Nematodes possess a closed circulatory system. Both nematodes and arthropods must molt in order to increase in size. Both nematodes and arthropods have segmented body plans.