Question 1

If an autotrophic Euglena species in pond water were placed in the dark, it would most likely
A) stop using its chloroplasts to synthesize organic compounds.
B) produce an excess of photosynthetic pigment.
C) begin using its chloroplast to synthesize organic compounds.
D) digest its chloroplast to obtain energy.
E) die.

Accepted Answer

Autotrophic Euglena species use their chloroplasts to undergo photosynthesis and create organic compounds. In the absence of light, they would not be able to perform photosynthesis, so they would stop using their chloroplasts to synthesize organic compounds.

Question 2

Which statement about the process of conjugation is false?
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.

Accepted Answer

Conjugation is not a reproductive process; it is a sexual process of genetic recombination where genetic material is exchanged between two organisms, but no new organisms are produced.

Question 3

Which group uses lobe-shaped pseudopods for locomotion?
A) Amoebozoans
B) Radiolarians
C) Euglenids
D) Foraminiferans
E) Ciliates

Accepted Answer

Amoebozoans are the only group among the given options that use lobe-shaped pseudopods for locomotion. Radiolarians use needle-like pseudopods for feeding, Euglenids use flagella for locomotion, Foraminiferans use needle-like pseudopods for feeding and chambered shells for locomotion, and ciliates use cilia for locomotion.

Question 4

A Paramecium individual contains two types of nuclei: a large macronucleus and as many as 80 micronuclei.The micronuclei are typical eukaryotic nuclei and are essential for genetic recombination.The macronucleus
A) is important in sexual recombination (conjugation).
B) contains many copies of the genetic information.
C) contains genetic information not found in the micronuclei.
D) contains DNA, but none of this DNA is transcribed.
E) contains DNA that is transcribed, but none of the transcripts are translated.

Accepted Answer

The macronucleus in Paramecium contains many copies of the genetic information, which is essential for the cell's everyday functioning, including the expression of genes necessary for the organism's metabolic, developmental, and physiological processes.

Question 5

After a particularly warm and wet summer, there is a spike in the population of tsetse flies in a rural sub-Saharan village.Many of the inhabitants begin to complain of fever and aching muscles.What might be the cause of their suffering?
A) The increase in tsetse flies has created more insect vectors for the kinetoplastid Trypanosoma brucei, resulting in more individuals struck by the sleeping sickness.
B) An increase in Trypanosoma brucei has provided the tsetse fly with an additional food supply, and the flies are now able to multiply more rapidly and bite more individuals.
C) Tsetse flies thrive on blood meals; their increase is a result of feeding on immunocompromised individuals.
D) Tsetse fly larvae attract water molds, resulting in contamination of the water supply and subsequent infection of humans by oomycete pathogens.
E) None of the above; the presence of the kinetoplastid Trypanosoma brucei is not related to the increase in the number of people suffering from the symptoms described.

Accepted Answer

The increase in tsetse flies provides more insect vectors for the kinetoplastid Trypanosoma brucei, which causes sleeping sickness. The fever and aching muscles described are symptoms of sleeping sickness.

Question 6

In the cellular slime molds, the onset of adverse conditions causes
A) an aggregation of myxamoebas to form a plasmodium.
B) the formation of sporangia.
C) the release of swarm cells from fruiting bodies.
D) the onset of cytoplasmic streaming.
E) an aggregation of myxamoebas to form a slug or pseudoplasmodium.

Accepted Answer

In cellular slime molds, adverse conditions trigger an aggregation of individual myxamoebas to form a multicellular structure called a slug or pseudoplasmodium. This structure moves as a unit to find a suitable location for the formation of a fruiting body, from which spores are eventually dispersed. The formation of sporangia and release of swarm cells from fruiting bodies occur at later stages of the life cycle, after the slug or pseudoplasmodium has formed. Cytoplasmic streaming is a common feature of many eukaryotic cells and is not specifically triggered by adverse conditions in cellular slime molds.

Question 7

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?
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.

Accepted Answer

The answer of Refer to the figure, which shows genetic...

Question 8

_______ are small _______ that use pseudopods to engulf small organisms and particles of organic matter.Some live in secreted shells (tests) or casings from sand particles glued together.
A) Cercozoans; rhizarians
B) Diatoms; stramenopiles
C) Dinoflagellates; alveolates
D) Loboseans; amoebozoans
E) Euglenids; excavates

Accepted Answer

The description matches that of loboseans, which are amoebozoans. They use pseudopods to engulf small organisms and particles of organic matter and can live in secreted shells or casings from sand particles glued together. The other choices do not match the given description.

Question 9

Which process is not part of conjugation in Paramecium?
A) Meiosis
B) Mitosis
C) Cytokinesis
D) Fusion of haploid nuclei
E) Breakdown of some micronuclei

Accepted Answer

Cytokinesis is not part of conjugation in Paramecium. Conjugation involves meiosis, mitosis, fusion of haploid nuclei, and breakdown of some micronuclei, but cytokinesis occurs after conjugation during cell division.

Question 10

Which of the following is not an asexual reproductive process among microbial eukaryotes?
A) Binary fission
B) Multiple fission
C) Budding
D) Spore formation
E) Meiosis

Accepted Answer

Meiosis is a sexual reproductive process that involves the formation of haploid gametes, which then fuse during fertilization to form a diploid zygote.

Therefore, the other choices (A, B, C, and D) are all asexual reproductive processes, where the parent cell divides to produce identical or nearly identical offspring without the involvement of gametes.

Question 11

Which statement concerning the spore-bearing fruiting structures produced by plasmodial slime molds is true?
A) Individual myxamoebas disperse
B) They contain diploid nuclei.
C) Their development is prompted by favorable conditions of moisture and food supply.
D) Knobs called sporangia develop at the end of the stalk of the fruiting structure.
E) The spores become diploid swarm cells that move by means of cilia.

Accepted Answer

The statement "Knobs called sporangia develop at the end of the stalk of the fruiting structure" is true for spore-bearing fruiting structures produced by plasmodial slime molds.

Question 12

Which statement about the micronucleus and macronucleus is false?
A) The macronucleus is involved in genetic recombination.
B) The micronucleus is a typical eukaryotic nucleus.
C) Multiple copies of macronuclear genes are commonly found.
D) Transcription and translation involve genes found mostly in the macronucleus.
E) The micronucleus and macronucleus are unique to ciliates.

Accepted Answer

The micronucleus is involved in genetic recombination, not the macronucleus. The macronucleus is responsible for gene expression and cell function, while the micronucleus is involved in sexual reproduction and the exchange of genetic material.

Question 13

Which protist group includes large multinucleate terrestrial heterotrophs that are visible to the naked eye and can be several yards in diameter?
A) Ciliates
B) Euglenids
C) Brown algae
D) Foraminiferans
E) Plasmodial slime molds

Accepted Answer

Plasmodial slime molds are the only protist group described that includes large multinucleate terrestrial heterotrophs that are visible to the naked eye and can be several yards in diameter.

Question 14

Which statement that does not describe a form of asexual reproduction found in protists.
A) Plasmodium sporozoites give rise to merozoites in the liver cells of humans.
B) Conjugation between two paramecia produces individuals that are genetically distinct from the original organisms.
C) Two daughter diatoms of dissimilar sizes (one smaller than the original) are produced during reproduction.
D) Myxamoebas cycle through slug and spore stages to produce new myxamoebas.
E) Euglenids produce new individuals primarily through binary fission.

Accepted Answer

Conjugation between two paramecia is a form of sexual reproduction, not asexual, because it involves the exchange of genetic material to produce genetically distinct individuals.

Question 15

Paramecia have an elaborate sexual behavior in which they line up against each other and fuse.This is followed by an extensive reorganization and exchange of nuclear material.The entire process is called
A) cloning.
B) alternation of generations.
C) sexual reproduction.
D) conjugation.
E) binary fission.

Accepted Answer

The described sexual behavior of paramecia involves lining up and fusing followed by the exchange of nuclear material, which is typical of conjugation in single-celled organisms. Therefore, choice D (conjugation) is the best choice. Choices A (cloning), B (alternation of generations), C (sexual reproduction), and E (binary fission) do not accurately describe the described behavior of paramecia.

Question 16

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 false?
A) The macronuclei in the resulting paramecia are genetically different from the macronuclei in the original paramecia.
B) The micronuclei that are exchanged are genetically different from each other.
C) Within each individual, the original macronucleus is destroyed.
D) The two resulting paramecia have a new combination of alleles that is different from the original.
E) The two resulting paramecia are genetically distinct from each other.

Accepted Answer

The answer of Refer to the figure, which shows genetic...

Question 17

Which statement regarding the role of meiosis in plasmodial slime molds is true?
A) Meiosis gives rise to the haploid nuclei that accumulate during the vegetative state of the slime mold.
B) During unfavorable conditions, plasmodial nuclei undergo meiosis before the organism creates a resting structure in the form of an irregular mass of hardened cell-like components.
C) During unfavorable conditions, plasmodial nuclei undergo meiosis before the sporangia develop on the fruiting structure.
D) The swarm cells of plasmodial slime molds divide by meiosis to produce haploid gametes.
E) Nuclei of plasmodial slime mold zygotes divide by meiosis to generate new coenocytic organisms.

Accepted Answer

Meiosis plays a role in the formation of the sporangia during the reproductive stage of plasmodial slime molds. When unfavorable conditions arise, the plasmodium undergoes meiosis to create haploid nuclei, which then differentiate into spores that develop into the sporangia on the fruiting body.

Question 18

Which term refers to a eukaryotic organism that undergoes alternation of generations in which different generations do not resemble each other morphologically?
A) Homomorphic
B) Heteromorphic
C) Isomorphic
D) Anisomorphic
E) Gametophytic

Accepted Answer

Heteromorphic refers to different generations having different morphologies, which is characteristic of organisms that undergo alternation of generations. Homomorphic refers to similar morphologies between different generations, while isomorphic refers to identical morphologies between different individuals. Anisomorphic and gametophytic are not relevant to this question.

Question 19

The difference between plasmodial slime molds and cellular slime molds is that
A) only cellular slime molds are motile.
B) they have different numbers of nuclei within the cell membrane.
C) only cellular slime molds ingest food by endocytosis.
D) only plasmodial slime molds ingest food by endocytosis.
E) cellular slime molds prefer cool, moist habitats, whereas plasmodial slime molds prefer dry, hot conditions.

Accepted Answer

Plasmodial slime molds are characterized by containing many nuclei enclosed within a single cell membrane, while cellular slime molds have individual cells that come together to form a larger structure. The other options presented are not accurate differences between the two types of slime molds.

Question 20

Which event is not normally associated with the life cycle of a plasmodial slime mold?
A) Development of spores into myxamoebas
B) Formation of an irregular mass when conditions are adverse
C) Active feeding by the plasmodium as it engulfs food particles
D) Production of sporangia through meiosis
E) Fusion of swarm cells to form a diploid zygote

Accepted Answer

Plasmodial slime molds, unlike cellular slime molds, do not have a stage where spores develop into myxamoebas. Instead, their life cycle typically involves the fusion of haploid cells to form a diploid zygote, which then grows into a multinucleate plasmodium.

Quiz 26: The Origin and Diversification of Eukaryotes

If an autotrophic Euglena species in pond water were placed in the dark, it would most likely

Which statement about the process of conjugation is false?

Which group uses lobe-shaped pseudopods for locomotion?

A Paramecium individual contains two types of nuclei: a large macronucleus and as many as 80 micronuclei.The micronuclei are typical eukaryotic nuclei and are essential for genetic recombination.The macronucleus

After a particularly warm and wet summer, there is a spike in the population of tsetse flies in a rural sub-Saharan village.Many of the inhabitants begin to complain of fever and aching muscles.What might be the cause of their suffering?

In the cellular slime molds, the onset of adverse conditions causes

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?

_ are small _ that use pseudopods to engulf small organisms and particles of organic matter.Some live in secreted shells (tests) or casings from sand particles glued together.

Which process is not part of conjugation in Paramecium?

Which of the following is not an asexual reproductive process among microbial eukaryotes?

Which statement concerning the spore-bearing fruiting structures produced by plasmodial slime molds is true?

Which statement about the micronucleus and macronucleus is false?

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

Which statement that does not describe a form of asexual reproduction found in protists.

Paramecia have an elaborate sexual behavior in which they line up against each other and fuse.This is followed by an extensive reorganization and exchange of nuclear material.The entire process is called

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 false?

Which statement regarding the role of meiosis in plasmodial slime molds is true?

Which term refers to a eukaryotic organism that undergoes alternation of generations in which different generations do not resemble each other morphologically?

The difference between plasmodial slime molds and cellular slime molds is that

Which event is not normally associated with the life cycle of a plasmodial slime mold?