Question 1

The demosponges

Accepted Answer

A)  constitute only a small number of species.
B)  are mostly marine but include the freshwater sponges.
C)  have the asconoid-type canal system.
D)  are referred to as calcium or chalk sponges.
E)  form the most beautiful glass spicule patterns.Members of the class Demospongia are the most common sponges.Most are large,leuconoid sponges.F) D) and E)
G) None of the above

Question 2

The extracellular matrix found in sponges is

Accepted Answer

A)  spongin.
B)  collagen.
C)  pinacoderm.
D)  mesohyl or mesenchyme.The gelatinous extracellular matrix,called mesohyle or mesenchyme,contains fibrils,skeletal elements and ameboid cells.E) A) and C)
F) B) and C) D

Question 3

The flagellated cells embedded in the mesohyl of a sponge are called ___________________.Choanocytes line the spongocoel and flagellated chambers of sponges.They propel water through a sponge and filter food from the water.

Accepted Answer

The answer of The flagellated cells embedded in the mesohyl...

Question 4

The largest impact that the loss of sponges would have on the environment would be

Accepted Answer

A)  collapse of most food chains.
B)  extinctions of other species that are symbionts of sponges.
C)  alteration of ocean currents.
D)  alteration of gases in water and the atmosphere.
E)  loss of filtration.Large sponges can filter up to 1,500 liters of water each day.Loss of this filtering would adversely affect water quality in marine habitats.F) C) and D)
G) B) and D)

Question 5

The order in which a drop of ink would pass by the structures in an ascon sponge is

Accepted Answer

A)  spongocoel-ostia-osculum.
B)  osculum-spongocoel-ostia.
C)  osculum-ostia-spongocoel.
D)  ostia-spongocoel-osculum.
E)  ostia-osculum-spongocoel.The pathway for water moving through the simplest sponge body form is ostia-spongocoel-osculum.In sycon sponges incurrent and radial canals are present.In leucon sponges the spongocoel is often absent.F) A) and C)
G) A) and E)

Question 6

Molecular data support the hypotheses that metazoans have a single origin or are _________________.

Accepted Answer

The answer of Molecular data support the hypotheses that metazoans...

Question 7

If a sponge is fragmented and cells are dissociated from one another,the cells will

Accepted Answer

A)  reproduce sexually.
B)  die from being separated.
C)  form spicules in the pattern of the cloth.
D)  reorganize their structure and function,and clumps of isolated cells will form a new sponge.Sponges have remarkable powers of regeneration from fragments of an organism and can undergo somatic embryogenesis when cells are dissociated into clumps of cells.E) All of the above
F) A) and B)

Question 8

Which of the following is NOT found in at least some sponges?

Accepted Answer

A)  Spicules of calcium carbonate
B)  Spicules of silica
C)  Spicules of fibrous protein
D)  Spongin,a fibrous protein Skeletal elements of sponges include calcareous and siliceous spicules and the protein,spongin.E) A) and B)
F) None of the above

Question 9

Specialized archaeocytes that secrete large quantities of collagen are

Accepted Answer

A)  collencytes.
B)  sclerocytes.
C)  choanocytes.
D)  spongocytes.
E)  lophocytes.Lophocytes are archeocytes specialized for secreting collagen.F) A) and D)
G) D) and E)

Question 10

About 80% of particulate organic carbon in the marine environment is in the form of the smallest particles that sponges can consume,and phagocytosis of these particles is carried out by the ____________.Choanocytes create water currents and filter particulate food matter from the water.

Accepted Answer

The answer of About 80% of particulate organic carbon in...

Question 11

The most complex and the most common body form of sponges is found in the

Accepted Answer

A)  asconoids.
B)  leuconoids.
C)  syconoids.Leuconoid sponges include the largest,most common,and most complex sponges.D) A) and B)
E) A) and C)

Question 12

Internal buds of freshwater sponges that can withstand adverse conditions are ____________________.Gemmules are found in freshwater and a few marine sponges.They are internal buds that withstand harsh environmental conditions.

Accepted Answer

The answer of Internal buds of freshwater sponges that can...

Question 13

Placozoans

Accepted Answer

A)  are flat,plate-like animals with no symmetry.
B)  are probably advanced mesozoans.
C)  have calcareous spicules.
D)  have three germ layers.Placozoans lack symmetry and any organs,muscular,and nervous tissues.Their dorsal and ventral epithelial layers may be ectodermal and endodermal tissue layers,thus some zoologists consider placozoans to be diplobastic.E) None of the above
F) A) and B)

Question 14

Explain the concept of monophyly as it applies to the animals.How do the relationships of placozoans and poriferans,as explained in this chapter,contribute to our understanding of the base of the animal tree shown on the inside cover of the book?

Accepted Answer

Monophyly refers to a group of organisms that includes a common ancestor and all of its descendants. In the context of animals, monophyly refers to a group that includes all animals that share a common ancestor and excludes any other organisms. This concept is important in understanding the evolutionary relationships and classification of animals.

The relationships of placozoans and poriferans contribute to our understanding of the base of the animal tree shown on the inside cover of the book because they help to determine the earliest branching events in animal evolution. Placozoans and poriferans are considered to be some of the simplest and most primitive animals, and their placement in the animal tree can provide insights into the early diversification of animal life.

By studying the relationships of placozoans and poriferans, scientists can gain a better understanding of the common ancestor of all animals and the evolutionary processes that led to the diversity of animal life we see today. This information can help to refine and improve the accuracy of the animal tree and our understanding of the evolutionary history of animals. Overall, the relationships of placozoans and poriferans contribute to our understanding of the base of the animal tree by providing important insights into the early stages of animal evolution.

Question 15

In glass sponges,archaeocytes fuse their pseudopodia to form a

Accepted Answer

A)  bud.
B)  spongin network.
C)  micropyle.
D)  leuconoid framework.
E)  trabecular reticulum.Hexactinellid sponges possess a unique syncytial body wall.All cells fuse into a single,multinucleate syncytum called the trabecular reticulum.F) A) and B)
G) C) and D)

Question 16

Specialized archaeocytes that secrete spicules are

Accepted Answer

A)  collencytes.
B)  sclerocytes.
C)  choanocytes.
D)  spongocytes.
E)  lophocytes.Archaeocytes may be specialized as sclerocytes,which secrete spicules.F) All of the above
G) B) and E) B

Question 17

Which of the following statements about sponges is NOT correct?

Accepted Answer

A)  Larvae are ciliated and swim to new locations
B)  Sponges are classified by spicule type and material
C)  Sponges comprise a sister group to all other animals
D)  Sponges share few characteristics with other animals
E)  Sponge cells can transform from one cell type to another,a trait not seen in other kinds of animals Sponges share many characteristics with other animals including the following: common adhesion proteins,a common blastula embryonic stage,and common cell signaling proteins.F) None of the above
G) All of the above

Question 18

The simplest of canal systems is found in the

Accepted Answer

A)  asconoids.
B)  leuconoids.
C)  syconoids.The asconoid sponge body form is the simplest of the sponge body forms.Larger,more complex sponge body forms are syconoid and leuconoid.D) A) and B)
E) A) and C)

Question 19

Concerning producing larger organisms without cellular differentiation,

Accepted Answer

A)  nature has never evolved larger organisms because it would never work.
B)  nature has evolved larger unicellular organisms but they are rare and have surface-to-volume limitations.
C)  this has never occurred since the ancestral cell was small.
D)  the more derived the organism,the more differentiated and the smaller the cell size.
E)  the more primitive the organism,the smaller the cell size.Larger size and complexity is accomplished through multicellularity.A workable surface-to-mass ratio in an increasingly large single cell cannot be maintained.F) D) and E)
G) C) and E)

Question 20

The outer thin,flat,epithelial-like cells that cover the outside and some inside surfaces of sponges,are

Accepted Answer

A)  amoebocytes.
B)  pinacocytes.
C)  choanocytes.
D)  spicules.
E)  spongin.Pinacocytes line the outer surface of the body wall of sponges.They may ingest food by phagocytosis and many are contractile to help regulate water flow.F) B) and C)
G) B) and E)

Exam 12: Sponges and Placozoans

The demosponges

Correct Answer
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The extracellular matrix found in sponges is

Correct Answer
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D

The flagellated cells embedded in the mesohyl of a sponge are called ___________________.Choanocytes line the spongocoel and flagellated chambers of sponges.They propel water through a sponge and filter food from the water.

Correct Answer
verified

The largest impact that the loss of sponges would have on the environment would be

Correct Answer
verified

The order in which a drop of ink would pass by the structures in an ascon sponge is

Correct Answer
verified

Molecular data support the hypotheses that metazoans have a single origin or are _________________.

Correct Answer
verified

If a sponge is fragmented and cells are dissociated from one another,the cells will

Correct Answer
verified

Which of the following is NOT found in at least some sponges?

Correct Answer
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Specialized archaeocytes that secrete large quantities of collagen are

Correct Answer
verified

About 80% of particulate organic carbon in the marine environment is in the form of the smallest particles that sponges can consume,and phagocytosis of these particles is carried out by the ____________.Choanocytes create water currents and filter particulate food matter from the water.

Correct Answer
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The most complex and the most common body form of sponges is found in the

Correct Answer
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Internal buds of freshwater sponges that can withstand adverse conditions are ____________________.Gemmules are found in freshwater and a few marine sponges.They are internal buds that withstand harsh environmental conditions.

Correct Answer
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Placozoans

Correct Answer
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Explain the concept of monophyly as it applies to the animals.How do the relationships of placozoans and poriferans,as explained in this chapter,contribute to our understanding of the base of the animal tree shown on the inside cover of the book?

In glass sponges,archaeocytes fuse their pseudopodia to form a

Correct Answer
verified

Specialized archaeocytes that secrete spicules are

Correct Answer
verified
B

Which of the following statements about sponges is NOT correct?

Correct Answer
verified

The simplest of canal systems is found in the

Correct Answer
verified

Concerning producing larger organisms without cellular differentiation,

Correct Answer
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The outer thin,flat,epithelial-like cells that cover the outside and some inside surfaces of sponges,are

Correct Answer
verified

Exam 12: Sponges and Placozoans

The demosponges

Correct AnswerverifiedShow Answer

The extracellular matrix found in sponges is

Correct AnswerverifiedD

The flagellated cells embedded in the mesohyl of a sponge are called ___________________.Choanocytes line the spongocoel and flagellated chambers of sponges.They propel water through a sponge and filter food from the water.

Correct AnswerverifiedShow Answer

The largest impact that the loss of sponges would have on the environment would be

Correct AnswerverifiedShow Answer

The order in which a drop of ink would pass by the structures in an ascon sponge is

Correct AnswerverifiedShow Answer

Molecular data support the hypotheses that metazoans have a single origin or are _________________.

Correct AnswerverifiedShow Answer

If a sponge is fragmented and cells are dissociated from one another,the cells will

Correct AnswerverifiedShow Answer

Which of the following is NOT found in at least some sponges?

Correct AnswerverifiedShow Answer

Specialized archaeocytes that secrete large quantities of collagen are

Correct AnswerverifiedShow Answer

About 80% of particulate organic carbon in the marine environment is in the form of the smallest particles that sponges can consume,and phagocytosis of these particles is carried out by the ____________.Choanocytes create water currents and filter particulate food matter from the water.

Correct AnswerverifiedShow Answer

The most complex and the most common body form of sponges is found in the

Correct AnswerverifiedShow Answer

Internal buds of freshwater sponges that can withstand adverse conditions are ____________________.Gemmules are found in freshwater and a few marine sponges.They are internal buds that withstand harsh environmental conditions.

Correct AnswerverifiedShow Answer

Placozoans

Correct AnswerverifiedShow Answer

Explain the concept of monophyly as it applies to the animals.How do the relationships of placozoans and poriferans,as explained in this chapter,contribute to our understanding of the base of the animal tree shown on the inside cover of the book?

In glass sponges,archaeocytes fuse their pseudopodia to form a

Correct AnswerverifiedShow Answer

Specialized archaeocytes that secrete spicules are

Correct AnswerverifiedB

Which of the following statements about sponges is NOT correct?

Correct AnswerverifiedShow Answer

The simplest of canal systems is found in the

Correct AnswerverifiedShow Answer

Concerning producing larger organisms without cellular differentiation,

Correct AnswerverifiedShow Answer

The outer thin,flat,epithelial-like cells that cover the outside and some inside surfaces of sponges,are

Correct AnswerverifiedShow Answer

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D

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B

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