Deck 18: Smaller Ecdysozoans

Question 1

Elephantiasis is an enlargement of legs,arms,scrotum,and other tissues caused by

A)an infection of the human coelom by Ascaris.
B)a large number of Trichinella worms encysting in our muscles.
C)contracting a disease that usually occurs in elephants.
D)microscopic nematodes that reproduce and clog lymph glands,causing infection and limbs to swell.
E)a protozoan that lives in tropical roundworms and which,when ingested by humans,causes muscles to bloat.

Answer 1

D

Question 2

In contrast to the function of our bodies,the nematode is unusual insofar as it

A)lacks circular muscles to antagonize the longitudinal muscles and must rely on the rigid cuticle and hydrostatic pressure.
B)extends muscle cells to the nerve process,rather than nerves to the muscle cells.
C)does not utilize the Krebs cycle and electron transport chain in anaerobic parasitic species.
D)moves food through its alimentary tract without direct muscle contractions on the intestine.
E)All of the choices are "unusual" nematode adaptations.

Answer 2

E

Question 3

Which of the following is NOT a factor that protects North Americans from many parasitic worm infections?

A)Much of the U.S.has bitter cold winters.
B)Most of the population wears shoes.
C)We usually cook our meat and there are few raw meat dishes.
D)We have superior drugs and surgeons.
E)We do not use human excreta ("night soil")to directly fertilize crops.

Answer 3

D

Question 4

If you are discovered to have an infection of Ascaris worms,your most likely danger is

A)anemia.
B)destruction of tissues as it migrates through your body.
C)blockage of the intestines.
D)starvation from lack of nutrition because it is absorbing all your food.
E)lymph blockage.

Question 5

If the main disease symptom is anemia (low red blood cell count),the most likely nematode parasite is

A)Trichinella.
B)Ascaris.
C)Pinworm.
D)Elephantiasis.
E)Hookworm.

Question 6

Juvenile Trichinella worms live in the

A)liver.
B)lungs.
C)intestines.
D)lymph glands.
E)skeletal muscle.

Question 7

Dogs commonly suffer from heartworm caused by

A)dirofilaria nematodes.
B)a tapeworm consumed in raw meat.
C)eating raw meat infected with Trichinella.
D)nematodes consumed as eggs in contaminated water.
E)None of the choices is correct.

Question 8

Which of the following statements is NOT correct about nematodes?

A)There are three layers of tissues in the body
B)Nematodes lack circular muscles under the tegument
C)The body cavity provides a hydrostatic skeleton
D)Nematodes have a smooth unsegmented outside body wall
E)Nematodes are all carnivores but may be free-living or parasitic

Question 9

Copulatory spicules function to

A)attract the female.
B)deliver sperm to the female vagina or gonopore.
C)hold the female vulva open against hydrostatic pressure.
D)store sperm in the male until copulation occurs.
E)store sperm in the female after copulation.

Question 10

The name "hookworms" is due to the fact they

A)cluster in blood vessels in the liver and clog the veins.
B)burrow constantly through muscle tissues.
C)hook onto the intestine and consume blood and tissue fluids causing anemia.
D)clog the lymph glands and expand the legs and arms.
E)have an anterior end that curves dorsally like a hook.

Question 11

In what two roundworm parasite cycles do worms get "coughed up" and swallowed in order to complete their cycle?

A)Ascaris and trichina
B)Ascaris and hookworm
C)Elephantiasis and trichina
D)Hookworm and trichina

Question 12

Which of these parasites does NOT enter the mouth of its human host and leave as eggs with the human feces?

A)Tapeworm
B)Pinworm
C)Ascaris
D)Hookworm
E)None of the choices is correct

Question 13

"If all the matter in the universe except the were swept away,our world would still be dimly recognizable,and if,as disembodied spirits,we could then investigate it,we should find its mountains,hills,vales,rivers,lakes,and oceans represented by a film of.The location of towns would be decipherable,since for every massing of human beings there would be a corresponding massing of certain.Trees would still stand in ghostly rows representing our streets and highways.The location of the various plants and animals would still be decipherable,and,had we sufficient knowledge,in many cases even their species could be determined by an examination of their erstwhile parasites." The missing term in this passage is

A)flatworms.
B)bacteria.
C)nematodes.
D)rotifers.
E)protozoans.

Question 14

Amphids and phasmids

A)are two kinds of nematodes.
B)perform a sensory function.
C)are found in the intestine.
D)are acquired by eating uncooked beef.
E)are reproductive stages in nematodes.

Question 15

The nematode Caenorhabditis elegans has allowed scientists to develop "fate maps" tracing cell lines back to cell origins.The trait of nematodes and some other related groups where they have a set number of cell divisions leading to the same number of body cells in an adult is called

A)anisogamy.
B)apoptosis.
C)cryptobiosis.
D)gastrulation.
E)eutely.

Question 16

Elephantiasis is transferred by

A)eating uncooked elephant meat.
B)worms burrowing into skin of feet.
C)drinking contaminated water or food.
D)mosquitoes injecting larval worms into the bloodstream.
E)exchanging body fluids with an infected person.

Question 17

The mild nematode infection somewhat common among children in the southern U.S. ,and transmitted as eggs from anal to oral regions by the hands is

A)Trichinella.
B)Ascaris.
C)Pinworm.
D)Elephantiasis.
E)Hookworm.

Question 18

Which of these is NOT a nematode?

A)Ascaris
B)Trichinella
C)Wuchereria
D)Hookworm
E)Schistosoma mansoni,a worm that causes schistosomiasis

Question 19

The parasite found in the U.S.where people contract it by eating poorly cooked pork,bear meat,etc.is

A)Trichinella.
B)Ascaris.
C)Pinworm.
D)Elephantiasis.
E)Hookworm.

Question 20

How do you become infected with Necator americanus hookworms?

A)You consume contaminated water or food
B)You eat uncooked meat
C)Larvae burrow into your feet
D)Mosquitoes inject them into your bloodstream
E)You transfer them from your anal region if you don't wash your hands

Question 21

Loriciferans

A)are tiny,about 0.10 to 0.50 mm long.
B)live in spaces between grains of marine gravel.
C)widely distributed in the world.
D)are dioecious.
E)All of the choices are correct.

Question 22

Filarial worms (Wuchereria and Brugia)are transmitted by _________________.

Question 23

The _______________ are burrowing marine worms with a proboscis,trunk,and usually one or two caudal appendages.

Question 24

Most male nematodes bear a pair of ________ ________ at their posterior end to aid in insemination of the female.

Question 25

Adult Ascaris worms are found in the host's _________________.or

Question 26

Nematodes have no circular muscles in the body wall;therefore,the ___________ antagonizes the longitudinal muscles.

Question 27

The outer body covering of a nematode is a relatively thick,noncellular cuticle,which is constructed primarily of a protein known as _______.

Question 28

Describe the life cycle of a Trichinella worm.

Question 29

The entire forepart of the body of a loricifera can be withdrawn into the __________________.

Question 30

Members of the phylum Priapulida

A)are metameric.
B)are coelomate because they have a peritoneum.
C)are hermaphroditic.
D)have a proboscis.
E)are active predators that pursue prey.

Question 31

Humans are infected with Trichinella spiralis by eating insufficiently cooked ______________.

Question 32

What feature do Tardigrades and arthropods share?

A)Three caudal lobes on the posterior end
B)Muscles that insert on setae
C)A small retractable proboscis
D)A thick non cellular cuticle
E)All are shared features

Question 33

Infective juveniles of hookworms gain access to a host by penetration of the ____________.

Question 34

The infective stage of Ascaris is the _____________,which is resistant to adverse conditions.

Question 35

Tiny marine worms that burrow through mud by extending the head and anchoring it by recurved spines are ________________.

Question 36

Nematomorphs

A)are called spiny-headed worms.
B)are rare.
C)are found in the host's liver.
D)are free-living as adults but parasitic on vertebrates as juveniles.
E)are free-living as adults but parasitic on arthropods as juveniles.

Question 37

The most common helminth parasite in the United States is the _________________.

Question 38

Nematodes have a fluid-filled pseudocoel that serves as a _____________ skeleton.

Question 39

Kinorhynchs

A)are relatively large (10 to 12.5 cm [4 to 5 in.]).
B)live in fresh water.
C)possess external cilia.
D)have a vestigial digestive system and absorbs food through its epidermis.
E)are marine worms.

Question 40

Onychophorans are also known as ___________ or walking worms.

Question 41

Discuss the structure and formation of the noncellular cuticle of nematodes.

Question 42

Outline the mode of infection of two of the following: hookworm,pinworm,intestinal roundworm,and trichina worm.

Question 43

On what bases do scientists suspect that the nematodes may be even more diverse than the insects?

Question 44

Explain why the Tardigrada and Onychophora are lumped with Arthropoda in the clade Panarthropoda.

Question 45

What specific factors protect the average North American from all of the parasitic cycles of flukes,tapeworms,and roundworms,etc.? Be sure to address social attitudes,clothing,climate,food preparation,use of human wastes as fertilizer,general medical care,sanitation facilities,and economics.

Question 46

Outline the life cycle of Wuchereria bancrofti.

Question 47

Give the reasoning behind the more recent classification of the clades Lophotrochozoa and Ecdysozoans.