Deck 12: Smaller Ecdysozoans

Question 1

The terrestrial tardigrades cannot withstand harsh environmental conditions.

Answer 1

False

Question 2

The Kinorhyncha are tiny marine worms.

Answer 2

True

Question 3

Sperm of nematodes are unusual in that they

A)lack a flagellum.
B)are diploid.
C)are cryptobiotiC.
D)possess an acrosome.
Fill in the Blank Questions

Answer 3

A

Question 4

The Onychophora and Tardigrada share some arthropod-like characteristics.

Question 5

Nematodes have circular muscles,but no longitudinal muscles in their body wall.

Question 6

Juvenile trichina worms live in the

A)skeletal muscle.
B)intestine.
C)lungs.
D)liver.

Question 7

Nematodes

A)possess flame cells.
B)possess an incomplete digestive tract.
C)are dioecious.
D)have external cilia.

Question 8

Nematomorphs

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

Question 9

Onychophorans

A)share some characteristics with annelids and some with arthropods.
B)are called water bears.
C)are marine.
D)feed on fish.

Question 10

A nematomorph worm is responsible for causing river blindness in many tropical areas.
Multiple Choice Questions

Question 11

The onychophorans have varied reproductive strategies;some are viviparous,some are oviparous and others are _____________.

Question 12

Tardigrades

A)are mostly marine.
B)have jointed legs.
C)have a cuticle.
D)appear to be closely related to kinorhynchs.

Question 13

Caterpillar-like animals found in humid,mostly tropical habitats belong to the phylum ___________.

Question 14

Female pinworms migrate out the anus to lay their eggs.

Question 15

Minute,mostly terrestrial animals living in the water film that surrounds mosses and lichens belong to the phylum ____________.

Question 16

Most nematode worms are under 5 cm long,but some are over a meter in length.

Question 17

A state in which metabolism is extremely low,and in which the water content of the body is reduced to a few percent,is called ___________.

Question 18

Elephantiasis is caused by filarial worms that live in the

A)muscles.
B)lymphatic system.
C)intestine.
D)lungs.

Question 19

The nematodes are the most diverse of the pseudocoelomates and include many important human parasites.

Question 20

Humans can get Ascaris parasites by ingestion of contaminated vegetables.

Question 21

Heavy infections of hookworms in human adults cause _____________.

Question 22

One of the most studied nematodes,whose genome is now known by geneticists is __________________.

Question 23

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

Question 24

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

Question 25

Nematodes have no circular muscles in the body wall;therefore,the __________ serves as the antagonist to the longitudinal muscles.

Question 26

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

Question 27

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

Question 28

Juvenile trichina worms cause the transformation of the host skeletal muscle cell into a _____________________ cell.

Question 29

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

Question 30

Adult Ascaris worms are found in the host's ______________.

Question 31

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

Question 32

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

Question 33

Nematodes only have _________________ muscles,which results in their characteristic thrashing movement.

Question 34

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

Question 35

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

Question 36

Many of the parasitic nematodes gain energy via ___________________ metabolism.

Question 37

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

Question 38

The entire forepart of the body of a loriciferan can be withdrawn into the ________________.

Question 39

Long and chronic infection with Wuchereria can result in _______________.