Question 1

The simplest body plan of sponges is ____________,and the plan characterized by flagellated canals is leuconoids.
Simple vase-like asconoid sponges are the simplest sponges.

Accepted Answer

The answer of The simplest body plan of sponges is...

Question 2

All digestion in sponges is intracellular and is carried out by the ____________________.
Choanocytes pass filtered food to archeocytes,which digest the food intracellularly.

Accepted Answer

The answer of All digestion in sponges is intracellular and...

Question 3

Explain the unique attributes of hexactinellids as compared to other sponges.

Accepted Answer

Hexactinellids, also known as glass spon...

Question 4

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) All of the above B

Question 5

The sponges date back to

Accepted Answer

A)   the Devonian period or "age of fishes."
B)   the early time of anaerobic prokaryotes.
C)   the Cambrian period and probably earlier.
D)   the time of the first prokaryotes but the sponges left no fossil evidence for lack of hard parts.Ancestral members of the phylum Porifera arose at least by the early Cambrian period and probably into Precambrian times. Later evolution resulted in diversification into the classes present today.E) B) and D)
F) A) and B)

Question 6

The structural protein found in all sponges is

Accepted Answer

A)   elastin.
B)   collagen.
C)   gorgonin.
D)   spiculin.
E)   None of the choices are correctCollagen is a connective protein common to all sponges.F) B) and D)
G) None of the above

Question 7

Describe the characteristics of the Phylum Porifera. Which of those characteristics support the contention that the sponges are the basal group of the Animal kingdom?

Accepted Answer

The Phylum Porifera, also known as spong...

Question 8

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 9

The free-swimming larva of most sponges is a

Accepted Answer

A)   bud.
B)   gemmule.
C)   apopyle.
D)   parenchymula.
E)   plasmodium.Parenchymula larvae are free-swimming larval stages found in the development of most sponges. Gemmules are internal buds found in freshwater sponges and some marine sponges.F) C) and D)
G) A) and C)

Question 10

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 proteinSkeletal elements of sponges include calcareous and siliceous spicules and the protein, spongin.E) All of the above
F) B) and D)

Question 11

There are a few marine sponges that are large enough that a small person could crawl inside.Would you have to worry about your tissues being digested?

Accepted Answer

Marine sponges, known scientifically as ...

Question 12

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) A) and B)
F) A) and D)

Question 13

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) B) and C)
F) A) and D) D

Question 14

Specialized archaeocytes that secrete spongin are

Accepted Answer

A)   collencytes.
B)   sclerocytes.
C)   choanocytes.
D)   spongocytes.
E)   lophocytes.Spongocytes are archeocytes specialized for secreting spongin.F) None of the above
G) A) and D)

Question 15

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) A) and B)
F) B) and C)

Question 16

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

choanocytes

Question 17

Molecular data support the hypotheses that metazoans have a single origin or are _________________.
Sponges are monophyletic. They arose from a single common ancestor. All other animals comprise a sister group to the sponges.

Accepted Answer

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

Question 18

Which of the following statements about sponges is NOT correct?

Accepted Answer

A)   Sponges lack nerve fibers
B)   Sponges lack fully developed muscle fibers
C)   Ameboid cells capture food particles from the water
D)   Sponges reproduce asexually by budding or by regeneration from a small piece
E)   If a sponge is fragmented and cells dissociate, cells undergo somatic embryogenesis and clumps of cells can form a new organismChoanocytes create water currents, capture food, and pass food on to ameboid cells.F) A) and E)
G) B) and D)

Question 19

Which one of the following statements regarding metazoan origins is true?

Accepted Answer

A)   Origin of the metazoa has been clearly elucidated and involves ancestry from a colonial flagellate stock.
B)   Metazoans are derived twice. One lineage involves a colonial flagellate stock, and the other lineage involves placozoan-like ancestors.
C)   Metazoans arose from a multinucleate ciliate where cell boundaries eventually formed around each nucleus.
D)   Placozoans may be similar to the single ancestral state. Features like their small nuclear genome and their large mitochondrial genome are features that may be derived from a common ancestor shared with some animal outgroups.The nuclear and mitochondrial genomes of the Placozoa suggest ancestry with animal outgroups.E) A) and D)
F) B) and D)

Question 20

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...

Exam 12: Sponges and Placozoans

The simplest body plan of sponges is ____________,and the plan characterized by flagellated canals is leuconoids. Simple vase-like asconoid sponges are the simplest sponges.

Correct AnswerverifiedShow Answer

All digestion in sponges is intracellular and is carried out by the ____________________. Choanocytes pass filtered food to archeocytes,which digest the food intracellularly.

Correct AnswerverifiedShow Answer

Explain the unique attributes of hexactinellids as compared to other sponges.

Correct AnswerAnswered by ExamLex AIHexactinellids, also known as glass spon...View AnswerShow Answer

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

Correct AnswerverifiedB

The sponges date back to

Correct AnswerverifiedShow Answer

The structural protein found in all sponges is

Correct AnswerverifiedShow Answer

Describe the characteristics of the Phylum Porifera. Which of those characteristics support the contention that the sponges are the basal group of the Animal kingdom?

Correct AnswerAnswered by ExamLex AIThe Phylum Porifera, also known as spong...View AnswerShow 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

The free-swimming larva of most sponges is a

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

There are a few marine sponges that are large enough that a small person could crawl inside.Would you have to worry about your tissues being digested?

Correct AnswerAnswered by ExamLex AIMarine sponges, known scientifically as ...View AnswerShow Answer

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

Correct AnswerverifiedShow Answer

The extracellular matrix found in sponges is

Correct AnswerverifiedD

Specialized archaeocytes that secrete spongin are

Correct AnswerverifiedShow Answer

Placozoans

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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 Answerverifiedchoanocytes

Molecular data support the hypotheses that metazoans have a single origin or are _________________. Sponges are monophyletic. They arose from a single common ancestor. All other animals comprise a sister group to the sponges.

Correct AnswerverifiedShow Answer

Which of the following statements about sponges is NOT correct?

Correct AnswerverifiedShow Answer

Which one of the following statements regarding metazoan origins is true?

Correct AnswerverifiedShow Answer

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

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Answered by ExamLex AI
Hexactinellids, also known as glass spon...
View Answer

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B

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Answered by ExamLex AI
The Phylum Porifera, also known as spong...
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Answered by ExamLex AI
Marine sponges, known scientifically as ...
View Answer

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D

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choanocytes

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