Chapter 33 - Invertebrates

Question 1

A sponge’s structural materials (spicules, spongin) are manufactured by the

A) pore cells.
B) epidermal cells.
C) choanocytes.
D) amoebocytes.

Answer 1

D) amoebocytes.

Question 2

How many of the following can be observed in the mesohyl of various undisturbed sponges at one time or another?

1. amoebocytes
2. spicules
3. spongin
4. zygotes
5. choanocytes

A) one of these
B) two of these
C) three of these
D) four of these
E) five of these

Answer 2

D) four of these

Question 3

Which chemical is synthesized by some sponges and acts as an antibiotic?

A) streptomycin
B) spongin
C) calcium carbonate
D) silica
E) cribrostatin

Answer 3

E) cribrostatin

Question 4

In terms of food capture, which sponge cell is most similar to the cnidocyte of a cnidarian?

A) amoebocyte
B) choanocyte
C) epidermal cell
D) pore cell

Answer 4

B) choanocyte

Question 5

Sponges are most accurately described as

A) marine predators.
B) marine filter feeders.
C) freshwater scavengers.
D) aquatic filter feeders.
E) aquatic predators.

Answer 5

D) aquatic filter feeders.

Question 6

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

A) one of these
B) two of these
C) three of these
D) four of these
E) five of these

Answer 6

D) four of these

Question 7

Which of the following is true of members of the phylum Cnidaria?

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

Answer 7

D) They may use a gastrovascular cavity as a hydrostatic skeleton.

Question 8

Which characteristic(s) is (are) shared by both cnidarians and flatworms?

A) dorsoventrally flattened bodies
B) true muscle
C) radial symmetry
D) a digestive system with a single opening
E) two of these

Answer 8

D) a digestive system with a single opening

Question 9

Against which hard structure do the circular and longitudinal muscles of annelids work?

A) bristles
B) cuticle
C) shell
D) endoskeleton
E) hydrostatic skeleton

Answer 9

E) hydrostatic skeleton

Question 10

What would be the most effective method of reducing the incidence of blood flukes in a human population?

A) reduce the mosquito population
B) reduce the freshwater snail population
C) purify all drinking water
D) avoid contact with rodent droppings
E) carefully wash all raw fruits and vegetables

Answer 10

B) reduce the freshwater snail population

Question 11

The larvae of many common tapeworm species that infect humans are usually found

A) encysted in freshwater snails.
B) encysted in the muscles of an animal, such as a cow or pig.
C) crawling in the abdominal blood vessels of cows and pigs.
D) crawling in the intestines of cows and pigs.

Answer 11

B) encysted in the muscles of an animal, such as a cow or pig.

Question 12

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)

A) chordate.
B) echinoderm.
C) mollusc.
D) nematode.
E) arthropod.

Answer 12

C) mollusc.

Question 13

A brachiopod can be distinguished from a bivalve by the presence of

A) two hinged shells.
B) a digestive system with separate mouth and anus.
C) a lophophore.
D) suspension feeding.
E) a distinct head.

Answer 13

C) a lophophore.

Question 14

If a lung were to be found in a mollusc, where would it be located?

A) mantle cavity
B) coelom
C) incurrent siphon
D) visceral mass
E) excurrent siphon

Answer 14

A) mantle cavity

Question 15

Which of the following is found only among annelids?

A) a hydrostatic skeleton
B) segmentation
C) a clitellum
D) a closed circulatory system
E) a cuticle made of chitin

Answer 15

C) a clitellum

Question 16

Which of the following is a characteristic of nematodes?

A) All species can be characterized as scavengers.
B) They have only longitudinal muscles.
C) They have a true coelom.
D) They have a gastrovascular cavity.
E) Many species are diploblastic.

Answer 16

B) They have only longitudinal muscles.

Question 17

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

A) one of these
B) two of these
C) three of these
D) four of these
E) five of these

Answer 17

C) three of these

Question 18

Nematode worms and annelid worms share which of the following features?

A) use of fluid in the body cavity as a hydrostatic skeleton
B) ecdysis
C) presence of a circulatory system
D) presence of segmentation
E) absence of species with parasitic lifestyles

Answer 18

A) use of fluid in the body cavity as a hydrostatic skeleton

Question 19

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 ________.

A) Platyhelminthes; a cuticle of chitin
B) Nematoda; an alimentary canal
C) Annelida; a body cavity
D) Nematoda; a circulatory system
E) Annelida; muscle in the body wall

Answer 19

D) Nematoda; a circulatory system

Question 20

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?

A) Platyhelminthes
B) Arthropoda
C) Nematoda
D) Acoela
E) Annelida

Answer 20

C) Nematoda

Question 21

Infection with which parasite might cause excessive elasticity in human skeletal muscles?

A) trichinella worms
B) tapeworms
C) copepods
D) blood flukes
E) rotifers

Answer 21

A) trichinella worms

Question 22

Which of the following are entirely, or partly, composed of calcium carbonate?

A) spicules of siliceous sponges
B) coral animals' exoskeletons
C) molluscs' mantles
D) insects' cuticles
E) nematodes' cuticles

Answer 22

B) coral animals’ exoskeletons

Question 23

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

A) one of these
B) two of these
C) three of these
D) four of these
E) five of these

Answer 23

C) three of these

Question 24

Among the invertebrate phyla, phylum Arthropoda is unique in possessing members that have

A) a cuticle.
B) a ventral nerve cord.
C) open circulation.
D) wings.
E) segmented bodies.

Answer 24

D) wings.

Question 25

A shared derived characteristic for members of the arthropod subgroup that includes spiders would be the presence of: ``` A) chelicerae. B) an open circulatory system. C) an exoskeleton. D) a cuticle. E) a cephalothorax. ```

Answer 25

A) chelicerae.

Question 26

You find a small animal with eight legs crawling up your bedroom wall. Closer examination will probably reveal that this animal has ``` A) simple, but not compound, eyes. B) two pairs of antennae. C) a head, thorax, and abdomen. D) tracheae and spiracles. E) more than one of these. ```

Answer 26

A) simple, but not compound, eyes.

Question 27

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

Answer 27

C) the radically different appearance between adults and earlier life stages

Question 28

A terrestrial animal species is discovered with the following larval characteristics: exoskeleton, system of tubes for gas exchange, and modified segmentation. A knowledgeable zoologist should predict that the adults of this species would also feature: ``` A) eight legs. B) two pairs of antennae. C) a sessile lifestyle. D) an open circulatory system. E) parapodia. ```

Answer 28

D) an open circulatory system.

Question 29

The possession of two pairs of antennae is a characteristic of ``` A) spiders. B) insects. C) centipedes. D) millipedes. E) crustaceans. ```

Answer 29

E) crustaceans.

Question 30

Which of the following is a characteristic of adult echinoderms? ``` A) bilateral symmetry B) spiral cleavage C) gastrovascular cavity D) exoskeleton E) lophophore ```

Answer 30

A) bilateral symmetry

Question 31

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

Answer 31

B) Tubefeet provide motility in most species.

Question 32

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? A) the presence of what seems to be radial symmetry B) a hard covering made partly of calcium carbonate C) a digestive system with mouth and anus separate from each other D) a water vascular system E) a nervous system

Answer 32

D) a water vascular system

Question 33

Which of the following animal groups is entirely aquatic? ``` A) Mollusca B) Crustacea C) Echinodermata D) Nematoda E) Platyhelminthes ```

Answer 33

C) Echinodermata

Question 34

In a tide pool, a student encounters an organism with a hard outer covering that contains much calcium carbonate, an open circulatory system, and gills. The organism could potentially be a crab, a shrimp, a barnacle, or a bivalve. The presence of which of the following structures would allow for the most certain identification of the organism? ``` A) a mantle B) a heart C) a body cavity D) a filter-feeding apparatus E) eyes ```

Answer 34

A) a mantle

Question 35

Which of the following is a diploblastic phylum of aquatic predators? ``` A) Cnidaria B) Annelida C) Mollusca D) Arthropoda E) Echinodermata ```

Answer 35

A) Cnidaria