Deck 9: Multicellular and Tissue Levels of Organization

Question 1

The most complex sponge body form,the __________,is characterized by multiple oscula and a complex canal system where choanocytes reside in small chambers.

A)leucon
B)ascon
C)sycon
D)polyp
E)medusa

Answer 1

A

Question 2

Which of the following would NOT be found in the body of a sponge?

A)ameboid cells
B)choanocytes
C)pinacocytes
D)spicules
E)colloblasts

Answer 2

E

Question 3

This group of animals does not possess embryological tissue layers.

A)scyphozoans
B)ctenophorans
C)poriferans
D)anthozoans
E)hydrozoans

Answer 3

C

Question 4

__________ sponges have incurrent canals formed by infoldings of the body wall.

A)Sclerosponge
B)Sycon
C)Leucon
D)Calcisponge
E)Ascon

Question 5

Just underneath the pinacocyte layer of a sponge is a jellylike layer referred to as the

A)ectoderm.
B)endoderm.
C)mesoderm.
D)mesohyl.
E)endochyme.

Question 6

Which of the following items is NOT found in sponges?

A)choanocytes
B)tissues
C)pinacocytes
D)porocytes
E)mesohyl

Question 7

The porocytes of ascon sponges lead to the outside via openings called

A)spongocoels.
B)atriopores.
C)blastopores.
D)oscula.
E)ostia.

Question 8

Ctenophores move via bands of cilia called

A)lappets.
B)rhopalia.
C)comb rows.
D)acontia.
E)tentacles.

Question 9

Sponges may gain nutrition by all of the following modes EXCEPT

A)filtration.
B)trapping of food items by the collar.
C)active transport of nutrients.
D)phagocytosis.
E)active predation.

Question 10

The taxonomy of sponges is determined by

A)the shape of the choanocytes.
B)the complexity of the osculum.
C)the material that composes the skeleton.
D)the presence or absence of porocytes.
E)the shape of the body of the sponge.

Question 11

Excretion and gas exchange in sponges are accomplished by

A)active transport.
B)diffusion.
C)contractile vacuoles.
D)nephridia.
E)osmosis.

Question 12

The __________ is the simplest,but least common body form of sponge.

A)leucon
B)sycon
C)demosponge
D)ascon
E)sclerosponge

Question 13

Eggs and sperm of sponges are commonly formed from

A)pinacocytes.
B)porocytes.
C)choanocytes.
D)spongiocytes.
E)sclerocytes.

Question 14

The single large opening at the top of the spongocoel is the

A)osculum.
B)atriopore.
C)ostium.
D)mouth.
E)anus.

Question 15

Gemmules contain masses of __________ which can survive freezing or drying.

A)amoeboid cells
B)porocytes
C)choanocytes
D)spongin
E)pinacocytes

Question 16

One proposed mechanism for the evolution of multicellularity involves an ancestral multinucleate cell in which plasma membranes formed between nuclei,resulting in a multicellular organism.This proposed mechanism is referred to as the __________ hypothesis.

A)colonial
B)coenocytial
C)polyphyletic
D)metazoan
E)synthetic

Question 17

Contractile pinacocytes that can regulate water circulation in some sponges are called

A)spongiocytes.
B)choanocytes.
C)porocytes.
D)archeocytes.
E)amebocytes.

Question 18

The collar of a choanocyte

A)regulates the diameter of the osculum.
B)filters food from the water.
C)creates currents in the water.
D)regulates the diameter of the ostia.
E)secretes digestive enzymes.

Question 19

The unique adhesive cells of ctenophores are

A)statoblasts.
B)cnidoblasts.
C)colloblasts.
D)pleuroblasts.
E)statoliths.

Question 20

Freshwater (and some marine)sponges form resistant structures which function in asexual reproduction,called

A)brown bodies.
B)larvae.
C)statoblasts.
D)spores.
E)gemmules.

Question 21

Members of this cnidarian class include the sea anemones and coral.

A)Cubozoa
B)Anthozoa
C)Hydrozoa
D)Scyphozoa
E)Mesozoa

Question 22

Nerve cells of animals in this phylum are considered by many biologists to be the most primitive nervous elements in the animal kingdom.

A)Porifera
B)Ctenophora
C)Cnidaria
D)Mesozoa
E)Placozoa

Question 23

The __________ body form of a cnidarian is typically asexual and sessile.

A)sycon
B)polyp
C)ascon
D)leucon
E)medusa

Question 24

Until very recently,this class of Cnidarians was included within the class Scyphozoa.

A)Hydrozoa
B)Staurozoa
C)Cubozoa
D)Anthozoa
E)Metridium

Question 25

Cnidarians possess a ____________ skeleton.

A)calcium carbonate
B)silicon based
C)spongin
D)hydrostatic
E)cartilagenous

Question 26

The feeding polyps of an Obelia colony are called

A)hydranths.
B)gastrozooids.
C)gonozooids.
D)statocysts.
E)statoblasts.

Question 27

The main source of nutrient carbohydrates in coral come from

A)zooxanthellae.
B)captured prey.
C)rhopalia.
D)acontia.
E)ephyrae.

Question 28

Members of the phylum __________ are characterized by radial (or biradial)symmetry,diploblastic organization,a gastrovascular cavity,and cnidocytes.

A)Mesozoa
B)Placozoa
C)Cnidaria
D)Porifera
E)Ctenophora

Question 29

Which of the following is not a characteristic of animals in the phylum Cnidaria?

A)diploblastic, tissue level organization
B)gastrovascular cavity
C)nervous system in the form of a nerve net
D)bilateral symmetry in the adult form
E)specialized cells called cnidocytes

Question 30

The free swimming larva of cnidarians is the

A)planula.
B)pilidium.
C)trochophore.
D)bipinnaria.
E)veliger.

Question 31

The __________ body form of a cnidarian is typically dioecious and motile.

A)sycon
B)polyp
C)ascon
D)leucon
E)medusa

Question 32

Members of the cnidarian class __________ never have a medusa stage.

A)Mesozoa
B)Hydrozoa
C)Scyphozoa
D)Anthozoa
E)Cubozoa

Question 33

Members of the phylum Ctenophora are commonly called

A)jellyfish.
B)comb jellies.
C)water bears.
D)ephyrae.
E)polyps.

Question 34

Members of class __________ are those historically used as commercial bath sponges.

A)Calcarea
B)Demospongiae
C)Hexactinellida
D)Syconidae
E)Leuconidae

Question 35

Sensory structures located in 8 notches around the bell of jellyfish medusae are

A)statoliths.
B)colloblasts.
C)manubri.
D)nematocysts.
E)rhopalia.

Question 36

Cnidarians exchange respiratory gases and nitrogenous wastes via

A)active pumping.
B)movement of cilia.
C)active transport.
D)movement of microvilli.
E)diffusion.

Question 37

The __________ cavity of cnidarians serves in digestion and as a site for exchange of respiratory gases and wastes.

A)intestine
B)spongocoel
C)gastrocoel
D)gastrovascular
E)archenteron

Question 38

An intracellular structure made of a fluid-filled capsule holding a coiled,hollow tube is the

A)cnidocyte.
B)choanocyate.
C)cnidocil.
D)nematocyst.
E)pinacocyte.