Question 1

Several eukaryote clades are referred to as "algae." The _______ algae are in the stramenopiles group.

Accepted Answer

The answer of Several eukaryote clades are referred to as...

Question 2

Refer to the gene tree shown.   Ribosomal RNA genes are present in the nuclear genomes of eukaryotes.There are also rRNA genes in the genomes of mitochondria and chloroplasts.Therefore photosynthetic eukaryotes have three different sets of rRNA genes, which encode the structural RNA of three separate sets of ribosomes.Translation of each genome takes place on its own set of ribosomes.The gene tree shows the evolutionary relationships among rRNA gene sequences isolated from the nuclear genomes of humans, yeast, and corn; from an archaeal species (Halobacterium), a proteobacterium (E.coli), and a cyanobacterium (Chlorobium); and from the mitochondrial and chloroplast genomes of corn.
Based on the gene tree, how would you explain the closer relationship of the mitochondrial rRNA gene of corn to the rRNA gene of E.coli rather than to the nuclear rRNA genes of other eukaryotes? Can you explain the relationship of the rRNA gene from the chloroplast of corn to the rRNA gene of the cyanobacterium?

Accepted Answer

The mitochondrial rRNA gene of corn is m

Question 3

Which statement about the process of conjugation is false?

Accepted Answer

A)  The disintegration of micronuclei is part of the process. 
B)  Meiosis takes place. 
C)  It is a reproductive process. 
D)  Mitosis takes place. 
E)  It is a sexual process of genetic recombination. 
A)  The disintegration of micronuclei is part of the process. 
B)  Meiosis takes place. 
C)  It is a reproductive process. 
D)  Mitosis takes place. 
E)  It is a sexual process of genetic recombination.

Question 4

Which features would most likely be characteristics of a protist with a multinucleate plasmodium that moves by cytoplasmic streaming and consumes yeasts, bacteria, and plant and animal remains via phagocytosis?

Accepted Answer

A)  Heterotrophy and quick movements in shallow freshwater ponds 
B)  Photosynthesis and a symbiotic relationship with oceanic radiolarians 
C)  Heterotrophy and slow movements over branches, rocks, and decaying logs 
D)  A secreted exoskeleton and floating movement among oceanic plankton 
E)  Multicellular form many meters long, supported by water, with a holdfast glued to rocks 
A)  Heterotrophy and quick movements in shallow freshwater ponds 
B)  Photosynthesis and a symbiotic relationship with oceanic radiolarians 
C)  Heterotrophy and slow movements over branches, rocks, and decaying logs 
D)  A secreted exoskeleton and floating movement among oceanic plankton 
E)  Multicellular form many meters long, supported by water, with a holdfast glued to rocks

Question 5

Which of the statement about diatoms is false?

Accepted Answer

A)  They produce a large portion of Earth's oxygen through photosynthesis. 
B)  They are endosymbiotic with corals. 
C)  They can form a major component of sedimentary rocks. 
D)  They have a great variety of intricate forms. 
E)  Their fossil remains are used in ecologically-friendly pesticides. 
A)  They produce a large portion of Earth's oxygen through photosynthesis. 
B)  They are endosymbiotic with corals. 
C)  They can form a major component of sedimentary rocks. 
D)  They have a great variety of intricate forms. 
E)  Their fossil remains are used in ecologically-friendly pesticides.

Question 6

Refer to the figure, which shows genetic recombination by conjugation in paramecia.   As it is shown in the figure, which statement about the conjugation process in paramecia is true?

Accepted Answer

A)  The two resulting paramecia are genetically different from the original. 
B)  The two resulting paramecia are genetically identical to the original. 
C)  Conjugation is a form of asexual reproduction. 
D)  The two resulting paramecia are genetically different from each other. 
E)  There is an unequal exchange of DNA between the paramecia. 
A)  The two resulting paramecia are genetically different from the original. 
B)  The two resulting paramecia are genetically identical to the original. 
C)  Conjugation is a form of asexual reproduction. 
D)  The two resulting paramecia are genetically different from each other. 
E)  There is an unequal exchange of DNA between the paramecia.

Question 7

If you discovered a unicellular parasite with a large mitochondrion containing a unique structure that housed multiple circular DNA molecules, you might conclude that the parasite is a _______.

Accepted Answer

kinetoplas

Question 8

Some euglenids are only able to obtain nutrition by engulfing particles and bacteria and are therefore considered _______.

Accepted Answer

The answer of Some euglenids are only able to obtain...

Question 9

Photosynthetic eukaryotes have genes for rRNA in their nuclei, mitochondria, and chloroplasts.Based on what you know about the origins of mitochondria and chloroplasts, which of the statements below would best describe the evolutionary relationship between the rRNA genes found in these three organelles?

Accepted Answer

A)  Nuclear and mitochondrial rRNA are derived from close relatives; however, both are distant from chloroplast rRNA. 
B)  Mitochondrial and chloroplast rRNA are derived from close relatives; however, both are distant from nuclear rRNA. 
C)  Nuclear and chloroplast rRNA are derived from close relatives; however, both are distant from mitochondrial rRNA. 
D)  Mitochondrial, chloroplast, and nuclear rRNA are all derived from distant relatives. 
E)  There is no reason to assume that any of the three rRNA genes are similar to closely or distantly related relatives. 
A)  Nuclear and mitochondrial rRNA are derived from close relatives; however, both are distant from chloroplast rRNA. 
B)  Mitochondrial and chloroplast rRNA are derived from close relatives; however, both are distant from nuclear rRNA. 
C)  Nuclear and chloroplast rRNA are derived from close relatives; however, both are distant from mitochondrial rRNA. 
D)  Mitochondrial, chloroplast, and nuclear rRNA are all derived from distant relatives. 
E)  There is no reason to assume that any of the three rRNA genes are similar to closely or distantly related relatives.

Question 10

Refer to the diagram, which shows the role of vacuoles in ciliate digestion.   Which of the following is a plausible hypothesis to explain why the vacuole color returns to red?

Accepted Answer

A)  The pH returns to basic because of increasing proton concentration. 
B)  The pH returns to basic because of decreasing proton concentration. 
C)  The dye from all food vacuoles coalesces into one vesicle destined for exocytosis. 
D)  Multiple food vacuoles at different stages of digestion fuse into a single vesicle. 
E)  The pH returns to acidic because of an increase in salt concentration. 
A)  The pH returns to basic because of increasing proton concentration. 
B)  The pH returns to basic because of decreasing proton concentration. 
C)  The dye from all food vacuoles coalesces into one vesicle destined for exocytosis. 
D)  Multiple food vacuoles at different stages of digestion fuse into a single vesicle. 
E)  The pH returns to acidic because of an increase in salt concentration.

Question 11

Which of the following are protists that do not use photosynthesis?

Accepted Answer

A)  Dinoflagellates 
B)  Algae 
C)  Plants 
D)  Slime molds 
E)  Euglenids 
A)  Dinoflagellates 
B)  Algae 
C)  Plants 
D)  Slime molds 
E)  Euglenids

Question 12

On a trip to the shore, you collect a sample of a brown alga and bring it back to your lab to investigate it further.Upon closer inspection, you notice that despite the consistent morphological appearance of your specimen, there is a mixture of haploid and diploid cells in your sample.What is a feasible explanation for this observation?

Accepted Answer

The species of brown alga that

Question 13

Which protist group includes large multinucleate terrestrial heterotrophs that are visible to the naked eye and can be several yards in diameter?

Accepted Answer

A)  Ciliates 
B)  Euglenids 
C)  Brown algae 
D)  Foraminiferans 
E)  Plasmodial slime molds 
A)  Ciliates 
B)  Euglenids 
C)  Brown algae 
D)  Foraminiferans 
E)  Plasmodial slime molds

Question 14

Which of the following have fossilized remains that are important components of limestone?

Accepted Answer

A)  Foraminiferans 
B)  Diatoms 
C)  Radiolarians 
D)  Brown algae 
E)  Ciliates 
A)  Foraminiferans 
B)  Diatoms 
C)  Radiolarians 
D)  Brown algae 
E)  Ciliates

Question 15

Which statement provides the best evidence of the relative ease with which multicellularity has evolved?

Accepted Answer

A)  Experimental studies have shown that in only a few months, multicellularity can be artificially selected for in some normally unicellular eukaryotic species. 
B)  Plasmodial slime molds, an early-diverging group of protists, are multicellular. 
C)  Multicellularity allows for nutrient and gas exchange over a larger surface area. 
D)  Some diatom species associate in filaments; such association is a precursor to multicellularity. 
E)  Cyanobacteria and other photosynthetic species are known to form floating rafts on the ocean's surface. 
A)  Experimental studies have shown that in only a few months, multicellularity can be artificially selected for in some normally unicellular eukaryotic species. 
B)  Plasmodial slime molds, an early-diverging group of protists, are multicellular. 
C)  Multicellularity allows for nutrient and gas exchange over a larger surface area. 
D)  Some diatom species associate in filaments; such association is a precursor to multicellularity. 
E)  Cyanobacteria and other photosynthetic species are known to form floating rafts on the ocean's surface.

Question 16

Which statement does not apply to apicomplexans?

Accepted Answer

A)  They are parasites. 
B)  They have complex life cycles. 
C)  They lack contractile vacuoles. 
D)  Each has an apical mass of organelles that helps it enter hosts. 
E)  Each possesses small sacs just below its cell membrane. 
A)  They are parasites. 
B)  They have complex life cycles. 
C)  They lack contractile vacuoles. 
D)  Each has an apical mass of organelles that helps it enter hosts. 
E)  Each possesses small sacs just below its cell membrane.

Question 17

Which group contains multicellular brown algae and giant kelps?

Accepted Answer

A)  Diplomonads 
B)  Chlorophytes 
C)  Stramenopiles 
D)  Alveolates 
E)  Euglenids 
A)  Diplomonads 
B)  Chlorophytes 
C)  Stramenopiles 
D)  Alveolates 
E)  Euglenids

Question 18

Which statement about brown algae is false?

Accepted Answer

A)  One genus floats in mats in the mid-Atlantic Sargasso Sea. 
B)  Silica-impregnated cell walls produce intricate patterns unique to each species. 
C)  A specialized holdfast aids in attachment to a surface. 
D)  Their chloroplasts contain the carotenoid fucoxanthin. 
E)  They are multicellular. 
A)  One genus floats in mats in the mid-Atlantic Sargasso Sea. 
B)  Silica-impregnated cell walls produce intricate patterns unique to each species. 
C)  A specialized holdfast aids in attachment to a surface. 
D)  Their chloroplasts contain the carotenoid fucoxanthin. 
E)  They are multicellular.

Question 19

The occurrence of primary endosymbiosis in the evolutionary past is supported by the existence of

Accepted Answer

A)  three membranes surrounding all chloroplasts. 
B)  three membranes surrounding all mitochondria. 
C)  peptidoglycan between the inner and outer membrane walls of chloroplasts. 
D)  two membranes surrounding the nucleus. 
E)  flagella consisting of microtubules. 
A)  three membranes surrounding all chloroplasts. 
B)  three membranes surrounding all mitochondria. 
C)  peptidoglycan between the inner and outer membrane walls of chloroplasts. 
D)  two membranes surrounding the nucleus. 
E)  flagella consisting of microtubules.

Question 20

Dinoflagellates are common endosymbionts of

Accepted Answer

A)  coral. 
B)  fungi. 
C)  other dinoflagellates. 
D)  tertiary endosymbionts. 
E)  stramenopiles. 
A)  coral. 
B)  fungi. 
C)  other dinoflagellates. 
D)  tertiary endosymbionts. 
E)  stramenopiles.

Exam 26: The Origin and Diversification of Eukaryotes

Several eukaryote clades are referred to as "algae." The _______ algae are in the stramenopiles group.

Which statement about the process of conjugation is false?

Which features would most likely be characteristics of a protist with a multinucleate plasmodium that moves by cytoplasmic streaming and consumes yeasts, bacteria, and plant and animal remains via phagocytosis?

Which of the statement about diatoms is false?

Refer to the figure, which shows genetic recombination by conjugation in paramecia. As it is shown in the figure, which statement about the conjugation process in paramecia is true?

If you discovered a unicellular parasite with a large mitochondrion containing a unique structure that housed multiple circular DNA molecules, you might conclude that the parasite is a _______.

Some euglenids are only able to obtain nutrition by engulfing particles and bacteria and are therefore considered _______.

Refer to the diagram, which shows the role of vacuoles in ciliate digestion. Which of the following is a plausible hypothesis to explain why the vacuole color returns to red?

Which of the following are protists that do not use photosynthesis?

Which protist group includes large multinucleate terrestrial heterotrophs that are visible to the naked eye and can be several yards in diameter?

Which of the following have fossilized remains that are important components of limestone?

Which statement provides the best evidence of the relative ease with which multicellularity has evolved?

Which statement does not apply to apicomplexans?

Which group contains multicellular brown algae and giant kelps?

Which statement about brown algae is false?

The occurrence of primary endosymbiosis in the evolutionary past is supported by the existence of

Dinoflagellates are common endosymbionts of

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