Zoology Test 2

Question 1

ctenophores:

Answer 1

have not advanced beyond the tissue grade of organization

Question 2

Not a characteristic of Phylum Platyhelminthes?

Answer 2

epidermal muscles

Question 3

the epidermal cells in ctenophores that function in prey are called:

Answer 3

colloblasts

Question 4

the flame cells or protonephridia of Platyhelminthes & rotifers:

Answer 4

function in osmoregulation and possibly waste removal

Question 5

mesoderm arises:

Answer 5

during blastopore formation (gastrulation)

Question 6

Tissues such as those found in parasitic platyhelminthes seem to violate the cell theory because the nuclei are not separated by cell membranes. The term used to describe these is:

Answer 6

syncytial

Question 7

the flukes in the class Monogenea:

Answer 7

are mostly ectoparasites

Question 8

the planarian (class turbellaraia) feeds by:

Answer 8

scraping and sucking food particles via a midventral proboscis

Question 9

head region of a tapeworm (class cestoda) is called:

Answer 9

scolex

Question 10

some parasites such as chlonorchis exhibit complex life cycles with many hosts and larval forms. Why do they do this?

Answer 10

to increase transmission rates & also so larval forms don’t compete with adults for same resources

Question 11

animals that have three layers of embryonic tissue but have organs in a cavity that is not completely lined with mesoderm are:

Answer 11

pseudocoelomate

Question 12

difference between schizocoelous and enterocoelous organism is

Answer 12

difference in how the true coelom forms from mesoderm: form the gut or blastopore region

Question 13

where would you locate the coelomic cavity when dissection a mollusk such as a clam?

Answer 13

the small cavity around the heart, kidney and lumen of the gonads

Question 14

which arose first in gastropods, coiling or torsion?

Answer 14

coiling

Question 15

a synapomorphy of all bivalves is:

Answer 15

no radula

Question 16

ctenidia are:

Answer 16

used for gas exchange

Question 17

the siphon in cephalopods is derived from the:

Answer 17

foot

Question 18

circulatory system of a squid is:

Answer 18

closed

Question 19

fastest means of cephalopod locomotion is

Answer 19

water (jet) propulsion

Question 20

the more advanced prosobranchs have only one …… in their mantle cavity

Answer 20

gill

Question 21

coiling in gastropods:

Answer 21

occurs when the mantle secretes more calcium carbonate on one side of the body versus the other

Question 22

coiling in cephalopods

Answer 22

occurred independently of coiling in gastropods

Question 23

which subclass of gastropoda do the nudibranchs belong to?

Answer 23

opisthobranchia

Question 24

snails that lack gills are called “pulmonate” and their mantle cavity functions:

Answer 24

as a lung

Question 25

the water current in the body of a cephalopod mollusk provides:

Answer 25

oxygen for respiration, jet power for rapid locomotion, a means for carrying wastes and gametes out of the body

Question 26

what is the advantage of the complex gut and muscular pharynx found in "advanced" Turbellarians?

Answer 26

increases surface area for digestion

Question 27

what is paedomorphosis?

Answer 27

retention of ancestral juvenile traits in adult body forms

Question 28

How many times has the eucolomate body plan evolved in animals?

Answer 28

3