Deck 20: Eukaryotic Diversity

Question 1

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

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

Answer 1

A

Question 2

All of the following are characteristics of eukaryotic organisms EXCEPT

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.

Answer 2

B

Question 3

Organisms in the ________ clade have lost their mitochondria through the process of reductive (degenerative) evolution.

A) Alveolata
B) Heterokonta
C) Opisthokonta
D) Metamonada
E) Discoba

Answer 3

D

Question 4

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

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

Question 5

What distinguishes the Opisthokonta from other eukaryotic clades?

A) an insertion coding for 11-17 amino acids in the elongation factor 1a gene
B) the sequence of ribosomal RNA genes
C) the sequence of RNA polymerase II
D) that some have a cell wall
E) that they are obligate heterotrophs

Question 6

Which of the following is NOT a common trait shared by most mycelium-forming fungi?

A) absorptive nutrition
B) hyphae production
C) multinucleated cells
D) chitinous cell walls
E) asexual reproduction by budding

Question 7

The oomycete ("water fungus") ________ caused the Great Irish Famine in the 1840s.

A) Opalina sp.
B) Tinea pedis
C) Phytophthora infestans
D) Amanita muscaria
E) Histoplasma capsulatum

Question 8

The following are ecological roles of fungi in nature EXCEPT

A) forming mycorrhizae that extend the root systems of plants and assimilate phosphorus.
B) nitrogen fixation in legume nodules.
C) recycling biomass of wood and leaves.
D) digestion of lignin, a component of wood.
E) fermentation of plant materials in the digestive tract of ruminants.

Question 9

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

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 10

The protozoa were considered to be microscopic animals because

A) they are bigger than bacteria.
B) of their capacity to cause disease.
C) of their ability to move.
D) some have proteinaceous cell walls.
E) some reproduce through conjugation.

Question 11

One of the smallest eukaryotes recently discovered, the green alga Ostreococcus tauri, measures less than ________ across and its genome (8 Mb) is ________ the size of that of Escherichia coli.

A) 2 mm; barely twice
B) 500 nm; half
C) 10 mm; about
D) 1 mm; three times
E) 100 mm; five times

Question 12

Which group has the widest range of form but the least diversity in terms of metabolism?

A) archaea
B) eukaryotes
C) bacteria
D) viruses
E) prokaryotes

Question 13

In the organism Saccharomyces cerevisiae, which of the following induces alternation of generations from a haploid to a diploid cell?

A) a 10°C decrease in optimum growth temperature
B) glucose abundance
C) starvation stress
D) nitrogen deprivation
E) a pH change toward acidic conditions

Question 14

What type of metabolism do eukaryotes conduct?

A) heterotrophy only
B) oxygenic photosynthesis only
C) oxygenic photosynthesis, heterotrophy, or both
D) ethanolic fermentation
E) mixed fermentation

Question 15

Which of the following is NOT a characteristic of fungi?

A) They are chemolithotrophs.
B) Most multicellular forms grow by extending multinucleate cell filaments called hyphae.
C) Membrane lipids include ergosterol, an analog of cholesterol.
D) Cell walls contain chitin.
E) They engage in absorptive nutrition.

Question 16

Which of the following is mismatched?

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

Neocallomastix sp. is/does NOT

A) classified as a Chytridiomycota.
B) an obligate aerobe.
C) possess flagellated reproductive forms called zoospores.
D) contain hydrogenosomes evolved from mitochondria.
E) ferment plant material in bovine rumen.

Question 18

The structure below represents the polysaccharide ________, which is the main component of cell walls in ________.

A) cellulose; Viridiplantae
B) murein; bacteria
C) chitin; fungi
D) starch; photosynthetic protists
E) hyaluronic acid; animals

Question 19

The figure below shows the cellular basis of extension of a fungal hypha. Which of the following is labeled correctly?

A) A-apical growth zone
B) B-absorption zone
C) C-vesicles
D) D-apical growth zone
E) E-storage zone

Question 20

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

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

Question 21

Dinoflagellates are marine phototrophs responsible for the toxic red tide blooms. What pigments confer the red color to these organisms?

A) rhodopsin
B) tannins
C) anthocyanins
D) chlorophylls
E) carotenoids

Question 22

Species in the genus ________ are unicellular green algae.

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

Question 23

Which of the following statements regarding pseudopods is NOT correct?

A) The term "pseudopods" means "false feet."
B) Amoebozoa have lobe-shaped pseudopods.
C) Lamellar pseudopods of amebas are similar to those generated by human leukocytes.
D) Needlelike pseudopods are thin extensions reinforced by myosin polymers.
E) The tip of a pseudopod contains a gel of polymerized actin beneath its cell membrane.

Question 24

Glomeromycota are obligate mutualists of plants

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.

Question 25

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

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 26

The slime mold Dictyostelium discoideum disperses spores fruiting body that are distributed by which means?

A) water currents
B) interacting with passing animals
C) air currents
D) gravity
E) piezoelectric force

Question 27

Which of the following algae reproduce by opposite mating filaments forming a cytoplasmic conjugate bridge to fuse cellular material?

A) filamentous green algae (Spirogyra)
B) sheet-forming red algae (Porphyra)
C) unicellular green algae (Chlamydomonas)
D) diatoms (Corethron)
E) foraminiferans (Globigerinella)

Question 28

The figure below is a schematic representation of Chlamydomonas life cycle. What is INCORRECTLY labeled?

A) A- mitosis
B) B-fusion of gametes
C) C-sexual reproduction
D) D-haploid asexual reproduction
E) E-zoospores

Question 29

Free living amebas are common soil predators that feed on bacteria, algae, rotifers, and so on. However, some species may harbor bacterial pathogens such as ________, which contaminates water supplies and air ducts.

A) Encephalitozoon intestinalis
B) Toxoplasma gondii
C) Leishmania major
D) Legionella pneumophila
E) Giardia lamblia

Question 30

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

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

Question 31

Encephalitozoon intestinalis is an organism classified as a Microsporidia. It is of clinical importance because it

A) causes severe allergic reactions in some people.
B) causes trypanosomiasis.
C) causes ringworm infections.
D) is an opportunistic pathogen in immunocompromised individuals.
E) infects catheters by producing biofilms.

Question 32

Which of the following is a signal for the slime mold Dictyostelium discoideum to switch from a unicellular state to an aggregate slug formation?

A) bacterial cell wall components (e.g., LPS, teichoic acids)
B) cyclic AMP
C) high glucose concentrations
D) increased light and warmth
E) actin polymerization

Question 33

Amanita phalloides makes a-amanitin, a dangerous toxin that can be used in the laboratory for studies in molecular biology. What enzyme is inhibited by a-amanitin?

A) RNA polymerase II
B) [H+]-ATPase
C) DNA polymerase III
D) gyrase
E) [Na+/K+]-ATPase

Question 34

Phytoplankton refers to

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.

Question 35

Some rhodophyta, or red algae, appear red due to the presence of the pigment

A) chlorophyll
B) chlorophyll
C) phycocyanin.
D) phycoerythrin.
E) anthocyanin.

Question 36

The following are characteristics of primary algae EXCEPT that

A) they are CO₂-fixing producers.
B) they all are single-celled organisms.
C) they have a cell wall made up of glycoprotein or cellulose.
D) chloroplasts are the result of a single endosymbiotic event.
E) they include the major clades Chlorophyta and Rhodophyta.

Question 37

Physarum polycephalum is a type of plasmodial slime mold that can be seen as a yellow mass growing on decaying wood. This organism produces

A) a fruiting body in which individual cells remain unicellular.
B) no fruiting bodies and no spore formations.
C) a giant multinucleated cell that produces fruiting bodies.
D) fruiting bodies within a calcified shell structure.
E) no fruiting bodies and spores that move using pseudopodia.

Question 38

A major group of marine phytoplankton that is essential to the marine food chain includes

A) microsporidia.
B) dinoflagellates.
C) apicomplexan.
D) metamonads.
E) yeasts.

Question 39

Paramecia beat their cilia in coordinated waves to

A) distract and fool predators.
B) move forward and acquire food.
C) attach to immobile structures for filter feeding.
D) deliver toxins to enemies.
E) accumulate minerals for shell synthesis.

Question 40

Ameboid movement is produced by

A) cytoplasmic streaming into the extending pseudopodia.
B) paired flagella formations extending off the cell membrane.
C) cilia structures surrounding the cell.
D) regulation of osmotic and gas vacuoles within the cytoplasm.
E) barophilic pumps within the cell membrane.

Question 41

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

Question 42

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

Question 43

The brewer's yeast Saccharomyces cerevisiae has been called a "single-celled" human because its genome of about 6,000 genes has many human homologs. Briefly describe three human cell processes that can be modeled using yeast.

Question 44

The apicomplexans have gone through extensive evolutionary reduction, in which the apicoplast has retained some genetic capabilities from an ancestral chloroplast in order to

A) allow only for phototrophic dark reactions.
B) produce low levels of ATP as backup metabolism.
C) fix carbon dioxide only.
D) absorb blue/green light only.
E) participate in fatty acid metabolism.

Question 45

Leishmania major infection is most problematic in

A) Central and South America.
B) South America, Africa, the Middle East, and southern Europe.
C) Sub-Saharan Africa.
D) eastern Europe and Central Asia.
E) the South Pacific.

Question 46

Trypanosomes are a group of organisms that share which of the following characteristics?

A) free-living aquatic parasites, round cell, no flagellum
B) intestinal parasites, shelled cell structure with pseudopodia
C) opportunistic parasites, multicellular with paired flagellum and apicoplast
D) obligate parasites, elongated cell with single flagellum and a kinetoplast
E) anaerobic parasites, single cellular structure with cilia

Question 47

Why are phylogenetic data in the domain Eukarya overall harder to obtain than phylogenetic evidence in either the Bacteria or Archaea domains? How has this affected the systematics of Eukarya?

Question 48

Use the figure below to describe the process of hyphal extension in fungi.

Question 49

Which of the following is a mismatched pair?

A) Trypanosoma brucei-sleeping sickness
B) Trypanosoma cruzi-Chagas disease
C) Balantidium coli-gastric ulcers
D) Entameba histolytica-amebiasis
E) Plasmodium falciparum-malaria

Question 50

Leishmania major causes a skin infection that can then disseminate to internal organs and is transmitted to a human host by

A) drinking contaminated water.
B) eating undercooked meat harboring the organism.
C) skin contact with someone carrying the disease.
D) bites from infected sand flies.
E) sexual transmission.

Question 51

Schizogony refers to the life-cycle stage of ________ in Plasmodium falciparum, which is found in the ________ stage.

A) mitotic reproduction and zygote development into spore-like form for transmission to next host; mosquito
B) mitotic reproduction to achieve large population within the vertebrate host; liver
C) meiotic reproduction to produce gametes; red-blood-cell
D) mitotic reproduction and zygote development into spore-like form for transmission to next host; red-blood-cell
E) meiotic reproduction to produce gametes; mosquito

Question 52

Why are sponges, jellyfish, worms, reptiles, humans, yeast, and microsporidia placed in the same eukaryotic clade?

Question 53

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.

Question 54

What are nanoeukaryotes and how has their discovery changed our understanding of biological systems?

Question 55

Giardia lamblia is an infectious problem in day-care centers because it is a(n) ________ pathogen passed via ________.

A) intestinal; water-borne transmission
B) aerosol; sneezing and coughing
C) mucosal; mucus contamination
D) skin; direct skin contact
E) blood-borne; contact with an open wound

Question 56

What are protists? What is the current status of the classification of protists? What is the difference between protozoa and protists?

Question 57

What are choanoflagellates and what is their importance in evolutionary studies?

Question 58

A kinetoplast is ________ containing a bundle of multiple copies of its circular genome.

A) a type of apicoplast
B) a relict chloroplast
C) mitochondrion
D) in the pseudopodia cytoplasm
E) inside a large chloroplast

Question 59

Plasmodium falciparum is a(n) ________ and is transmitted to the human host by the bite of a ________.

A) Apicomplexan; mosquito
B) type of Trypanosome; tsetse fly
C) Apicomplexan; reduviid bug
D) type of Trypanosome; mosquito
E) Apicomplexan; sand fly

Question 60

New and emerging drug therapy targets for Plasmodium falciparum include

A) spore-release inhibitors.
B) uncoupling agents.
C) conjugation inhibitors.
D) hemoglobin protease inhibitors.
E) cilia inhibitors.

Question 61

Compare and contrast radiolarians and foraminiferans.

Question 62

In the figure below, the letters A, B, and C represent the formation of Giardia intestinalis dormant cysts from trophozoites and back. Briefly describe the structure and life cycle of G. intestinalis. What conditions lead to the formation of the cyst?

Question 63

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.

Question 64

Use the figure below as a guide to describe the cycle of Plasmodium falciparum transmission between mosquito and human in malaria.

Question 65

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

Question 66

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

Question 67

Briefly describe the life cycle of Ascomyta and describe three ascomycetes that have been used in science or in the culinary arts.

Question 68

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

Question 69

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?

Question 70

Use the figure below to describe the mechanism of pseudopod motility in Amoebozoa.