Question 1

Compare and contrast radiolarians and foraminiferans.

Accepted Answer

Answers will vary.
Amebas that form needlelike pseudopods form the clade Rhizaria, which includes the interesting shelled amebas known as radiolarians and foraminiferans. Both groups grow in marine and freshwater habitats. The shell (or test) in radiolarians is made of silica, which is perforated, allowing the pseudopods to radiate in all directions, hence the name "radiolarian." Foraminiferans have shells formed of calcium carbonate arranged as chambers laid down in a helical manner; the pseudopods extend from one opening in the most recent chamber.
The shells are part of reefs, sedimentary rock, and beach sand. Foraminiferans are indicators of oil deposits in geological strata, as the shells fossilize well and can be found in some rock types that are associated with fossil fuels.

Question 2

Why would an organism benefit from undergoing more than one endosymbiotic event throughout evolution? Give an example to support your argument.

Accepted Answer

Answers will vary.
Primary endosymbiosis includes events that lead to the formation of a mitochondrion (from an ancestral proteobacterium) or a chloroplast (from an ancestral cyanobacterium). If an organism with a mitochondrion were then to undergo a secondary endosymbiosis event with an organism containing a chloroplast, this new organism would gain two different mechanisms of energy production, namely photosynthesis and aerobic respiration. While primarily phototrophic, some diatoms can live in the absence of light using heterotrophy, assuming that an appropriate carbon source is available. This gives such organisms the advantage to easily adapt to multiple environments.

Question 3

Phytoplankton refers to

Accepted Answer

A)  heterotrophic bacteria present in aquatic and marine environments. 
B)  mixotrophic algae and amebas present in aquatic environments. 
C)  photosynthetic algae and bacteria present in aquatic and marine environments. 
D)  heterotrophic algae, bacteria, and protists present in aquatic, marine, and terrestrial environments. 
E)  photosynthetic algae and plants present in aquatic, marine, and terrestrial environments. 
A)  heterotrophic bacteria present in aquatic and marine environments. 
B)  mixotrophic algae and amebas present in aquatic environments. 
C)  photosynthetic algae and bacteria present in aquatic and marine environments. 
D)  heterotrophic algae, bacteria, and protists present in aquatic, marine, and terrestrial environments. 
E)  photosynthetic algae and plants present in aquatic, marine, and terrestrial environments. C

Question 4

The figure below depicts two paramecia during conjugation. Use the numbered arrows to briefly describe the steps in this phenomenon. The figure can be used to describe what happens in one of the cells.

Accepted Answer

Initially, two paramecia of different ma

Question 5

All of the following are characteristics of eukaryotic organisms EXCEPT

Accepted Answer

A)  their cells possess a nucleus. 
B)  all types of eukaryotic cells are surrounded by a cell wall. 
C)  they are highly compartmentalized and have an endomembrane system. 
D)  they include organisms with unicellular complex multicellular bodies or unicellular forms. 
E)  they display aerobic respiration, although some are capable of phototrophy. 
A)  their cells possess a nucleus. 
B)  all types of eukaryotic cells are surrounded by a cell wall. 
C)  they are highly compartmentalized and have an endomembrane system. 
D)  they include organisms with unicellular complex multicellular bodies or unicellular forms. 
E)  they display aerobic respiration, although some are capable of phototrophy.

Question 6

Which organisms are considered the possible "missing link" in the evolution from microbial eukaryotes to multicellular animals due to shared genes?

Accepted Answer

A)  metazoa 
B)  slime molds 
C)  eumycota 
D)  choanoflagellata 
E)  microsporidia 
A)  metazoa 
B)  slime molds 
C)  eumycota 
D)  choanoflagellata 
E)  microsporidia

Question 7

Describe how the life cycle of the slime mold Dictyostelium discoideum is dependent upon prokaryotic organisms.

Accepted Answer

Haploid Dyctiostelium discoideum amebas

Question 8

The figure below shows the life cycle of an ascomycete. What is INCORRECTLY labeled?

Accepted Answer

A)  A-mitosis 
B)  B-pairing of nuclei 
C)  C-cytoplasmic fusion 
D)  D-hyphae containing paired nuclei grow into mycelia 
E)  E-nuclear fusion 
A)  A-mitosis 
B)  B-pairing of nuclei 
C)  C-cytoplasmic fusion 
D)  D-hyphae containing paired nuclei grow into mycelia 
E)  E-nuclear fusion

Question 9

Species in the genus ________ are unicellular green algae.

Accepted Answer

A)  Volvox 
B)  Porphyra 
C)  Spirogyra 
D)  Ulva 
E)  Chlamydomonas 
A)  Volvox 
B)  Porphyra 
C)  Spirogyra 
D)  Ulva 
E)  Chlamydomonas

Question 10

The Rhodophyta alga Porphyra is known to colonize aquatic environments deeper than the Chlorophyta algae Spirogyra. Why does this happen? What advantages does Porphyra have by inhabiting this niche?

Accepted Answer

The Rhodophyta, or red algae, are red du

Question 11

Why are coral endosymbionts, known as zooxanthellae, important indicators of ocean health?

Accepted Answer

The name "zooxanthellae" refers to the r

Question 12

Use the figure below and describe the differences between primary and secondary algae. Provide examples of both types.

Accepted Answer

Primary alga evolved from a single endos

Question 13

Amebas that have filopodial movement structures can be found in which categories?

Accepted Answer

A)  trypanosomes and metamonads 
B)  diatoms and algae 
C)  dinoflagellates and apicomplexans 
D)  cellular and plasmodial slime molds 
E)  radiolarians and foraminiferans 
A)  trypanosomes and metamonads 
B)  diatoms and algae 
C)  dinoflagellates and apicomplexans 
D)  cellular and plasmodial slime molds 
E)  radiolarians and foraminiferans

Question 14

The structural characteristic that defines the clade Heterokonta is that they all

Accepted Answer

A)  inhabit the same ecological niche. 
B)  rely exclusively on photosynthesis for metabolism. 
C)  have or have had pairs of flagella of different shapes and lengths. 
D)  have a bipartite shell called a frustule. 
E)  move with similar locomotive structures. 
A)  inhabit the same ecological niche. 
B)  rely exclusively on photosynthesis for metabolism. 
C)  have or have had pairs of flagella of different shapes and lengths. 
D)  have a bipartite shell called a frustule. 
E)  move with similar locomotive structures.

Question 15

The term "protist" describes single-cell and colonial eukaryotic organisms other than

Accepted Answer

A)  paramecia. 
B)  diatoms. 
C)  dinoflagellates. 
D)  fungi. 
E)  amebas. 
A)  paramecia. 
B)  diatoms. 
C)  dinoflagellates. 
D)  fungi. 
E)  amebas.

Question 16

Which of the following is mismatched?

Accepted Answer

A)  Ascomycota-Penicillium, yeasts, fungal component of lichens 
B)  Basidiomycota-Amanita, Licoperdon, Cryptococcus neoformans 
C)  Chytridiomycota-Batrachochytrium dendrobatidis, Neocallomastix 
D)  Zygomycota-saprophytes, insect parasites 
E)  Microsporidia-arbuscular mycorrhizae 
A)  Ascomycota-Penicillium, yeasts, fungal component of lichens 
B)  Basidiomycota-Amanita, Licoperdon, Cryptococcus neoformans 
C)  Chytridiomycota-Batrachochytrium dendrobatidis, Neocallomastix 
D)  Zygomycota-saprophytes, insect parasites 
E)  Microsporidia-arbuscular mycorrhizae

Question 17

The Zygomycota taxon comprises saprophytes, mycorrhiza, and insect parasites. They are characterized by having nonmotile gametes that must grow toward each other to fuse and form a zygote (zygospore). Explain why this taxon is classified under the larger taxa of Opisthokonta, which includes organisms with flagellated reproductive cells.

Accepted Answer

Zygomycota falls under the true fungi (E

Question 18

Describe how Trypanosoma brucei overwhelms the immune system of an infected animal host, and explain the possible current targets for drug therapy.

Accepted Answer

Trypanosoma brucei causes the African sl

Question 19

The following are examples of challenges for classification of eukaryotes, EXCEPT

Accepted Answer

A)  eukaryotic chromosomes are located inside the nucleus. 
B)  eukaryotes have experienced multiple endosymbiotic events. 
C)  genome size and complexity has delayed completion of genomic sequences. 
D)  for superficial similarity in form and habitat in distant taxa leading to convergent evolution. 
E)  within a clade, some cells have lost structures through reductive evolution; others have not. 
A)  eukaryotic chromosomes are located inside the nucleus. 
B)  eukaryotes have experienced multiple endosymbiotic events. 
C)  genome size and complexity has delayed completion of genomic sequences. 
D)  for superficial similarity in form and habitat in distant taxa leading to convergent evolution. 
E)  within a clade, some cells have lost structures through reductive evolution; others have not.

Question 20

Glomeromycota are obligate mutualists of plants

Accepted Answer

A)  that form fruiting bodies, such as basidiomycetes. 
B)  and are considered pathogenic to more than 90% of all land plants. 
C)  that form arbuscular mycorrhizae, in which fungal filaments surround the plant cell walls but do not penetrate them. 
D)  that receive sugars from plants and provide ammonium and phosphate to plants. 
E)  that form periarbuscular space within the fungi's own cell wall. 
A)  that form fruiting bodies, such as basidiomycetes. 
B)  and are considered pathogenic to more than 90% of all land plants. 
C)  that form arbuscular mycorrhizae, in which fungal filaments surround the plant cell walls but do not penetrate them. 
D)  that receive sugars from plants and provide ammonium and phosphate to plants. 
E)  that form periarbuscular space within the fungi's own cell wall.

Exam 20: Eukaryotic Diversity

Compare and contrast radiolarians and foraminiferans.

Why would an organism benefit from undergoing more than one endosymbiotic event throughout evolution? Give an example to support your argument.

Phytoplankton refers to

The figure below depicts two paramecia during conjugation. Use the numbered arrows to briefly describe the steps in this phenomenon. The figure can be used to describe what happens in one of the cells.

All of the following are characteristics of eukaryotic organisms EXCEPT

Which organisms are considered the possible "missing link" in the evolution from microbial eukaryotes to multicellular animals due to shared genes?

Describe how the life cycle of the slime mold Dictyostelium discoideum is dependent upon prokaryotic organisms.

The figure below shows the life cycle of an ascomycete. What is INCORRECTLY labeled?

Species in the genus ________ are unicellular green algae.

The Rhodophyta alga Porphyra is known to colonize aquatic environments deeper than the Chlorophyta algae Spirogyra. Why does this happen? What advantages does Porphyra have by inhabiting this niche?

Why are coral endosymbionts, known as zooxanthellae, important indicators of ocean health?

Use the figure below and describe the differences between primary and secondary algae. Provide examples of both types.

Amebas that have filopodial movement structures can be found in which categories?

The structural characteristic that defines the clade Heterokonta is that they all

The term "protist" describes single-cell and colonial eukaryotic organisms other than

Which of the following is mismatched?

Describe how Trypanosoma brucei overwhelms the immune system of an infected animal host, and explain the possible current targets for drug therapy.

The following are examples of challenges for classification of eukaryotes, EXCEPT

Glomeromycota are obligate mutualists of plants

Microbial Life: Origin and Discovery

Observing the Microbial Cell

Cell Structure and Function

Bacterial Culture, Growth, and Development

Environmental Influences and Control of Microbial Growth

Viruses

Genomes and Chromosomes

Transcription, Translation, and Bioinformatics

Gene Transfer, Mutations, and Genome Evolution

Molecular Regulation

Viral Molecular Biology

Biotechniques and Synthetic Biology

Energetics and Catabolism

Electron Flow in Organotrophy, Lithotrophy, and Phototrophy

Biosynthesis

Food and Industrial Microbiology

Origins and Evolution

Bacterial Diversity

Archaeal Diversity

Microbial Ecology

Microbes in Global Elemental Cycles

Human Microbiota and Innate Immunity

The Adaptive Immune Response

Microbial Pathogenesis

Microbial Diseases

Antimicrobial Therapy

Clinical Microbiology and Epidemiology

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