Name _____________________________________________ Date __________ Period ______
Multiple Choice
Directions: Read the statements below and circle the correct answer choice.
1. Vinegar eels, pinworms, and other round worms are classified into which phylum?
A. Acantocephala
B. Nematoda
C. Nematomorpha
D. Rotifera
2. Rotifers are classified into which phylum?
A. Acantocephala
B. Nematoda
C. Nematomorpha
D. Rotifera
3. Animals having a body cavity between the mesoderm and the endoderm that is not lined with mesenteries are known as __________________.
A. acoelomate
B. coelomate
C. hypercoelomate
D. hypocoelomate
E. pseudocoelomate
4. Which of the following is the purpose of a body cavity?
A. provides room for organ development
B. provides increased surface area for diffusion of gases
C. provides area for storage
D. acts as a hydrostatic skeleton
E. all of the above
5. What type of symmetry is exhibited by the phylum Rotifera?
A. asymmetry
B. bilateral
C. biradial
D. radial
E. pentaradial
6 . What is the purpose of a rotifer’s corona?
A. aids in locomotion
B. aids in protection
C. aids in feeding
D. aids in reproduction
E. both A and C are correct

7
. A rotifer’s pharynx contains a unique structure known as a ____________ which is a muscular organ that grinds food.
A. amphid
B. corona
C. mastax
D. phasmid
E. renette
8. Most organisms in the phylum Rotifera only have one opening to the digestive tract.
A. True
B. False
9. _______________ is a modified form of sexual reproduction in which the gametes develop without fertilization.
A. Binary fission
B. Conjugation
C. Parthenogenesis
D. Transverse fission
E. Fusion
10. The majority of rotifers inhabit freshwaters.
A. true
B. false
11. Organisms in the phylum Nematoda are triploblastic.
A. true
B. false
12. Most members of the phylum Nematoda are dioecious. What does this mean?
A. they have one body opening
B. they have two body openings
C. they produce one offspring at a time
D. male and female sex organs are in separate individuals
E. they have both male and female sex organs in the same individual
13. Nematodes live in both aquatic and terrestrial environments.
A. true
B. false
14. Nematodes move with a thrashing motion rather than the gliding motion seen in
Platyhelminthes. What is the anatomical reason for this difference?
A. Nematodes move using cilia
B. Nematodes only have longitudinal muscles
C. Nematodes only have circular muscles
D. Nematodes move using flagella
E. Nematodes have both longitudinal and circular muscles

15. Anterior depressions in the cuticle of nematodes that function in chemoreception are known as _______________.
A. amphids
B. ocelli
C. phasmids
D. protonehpridia
E. renettes
16. Nematodes are covered by a layered elastic cuticle. What is the function of this cuticle?
A. provides protection
B. resists digestion by the host
C. acts as a hydrostatic skeleton
D. all of the above
17. What is the name of the unique excretory structure of some roundworms?
A. amphid
B. kidney
C. phasmid
D. protonephridium
E. renette
18. Identify this organism.
A. Ascaris
B. Gastrotrich
C. Rotifer
D. Vinegar eel
19. Identify this organism.
A. Ascaris
B. Gastrotrich
C. Rotifer
D. Vinegar eel
20. Identify this organism.
A. Ascaris
B. Gastrotrich
C. Rotifer
D. Vinegar eel

21. Identify the structures on the organism on the right.
A
.
D
.
F.
E.
B.
C.