Bacteria, Archae And Protists Flashcards
A catabolic pathway in which inorganic molecules other than oxygen accept electrons at the “downhill” end of electron transport chains.
anaerobic respiration
Which of the following statements concerning living phytoplanktonic organisms are true?
1. They are important members of communities surrounding deep-sea hydrothermal vents;
2. They are important primary producers in most aquatic food webs;
3. They are important in maintaining oxygen in Earth’s seas and atmosphere;
4. They are most often found growing in the sediments of seas and oceans;
5. They can be so concentrated that they affect the colour of seawater.
A. 1 and 4.
B. 1, 2, and 4.
C. 2, 3, and 4.
D. 2, 3, and 5.
E. 3, 4, and 5.
D.
A gelatinous seaweed that grows in shallow, cold water and undergoes heteromorphic alternation of generations is most probably what type of alga?
A. red.
B. green.
C. brown.
D. yellow.
E. none of these.
C.
You are designing an artificial drug-delivery ʺcellʺ that can penetrate animal cells. Which of these protist structures should provide the most likely avenue for research along these lines?
A. pseudopods.
B. apical complex.
C. excavated feeding grooves. D. nucleomorphs.
E. mitosomes.
B.
You are given the task of designing an aerobic, mixotrophic protist that can perform photosynthesis in fairly deep water (e.g. 250 m deep), and can also crawl about and engulf small particles. With which two of these structures would you provide your protist? 1. Hydrogenosome; 2. Apicoplast; 3. Pseudopods; 4. Chloroplast from red alga; 5. Chloroplast from green alga.
A. 1 and 2. B. 2 and 3. C. 2 and 4. D. 3 and 4. E. 4 and 5.
D.
Which of the following correctly pairs a protist with one of its characteristics?
A. diplomonads – micronuclei involved in conjugation.
B. ciliates – pseudopods.
C. apicomplexans – parasitic.
D. gymnamoebas – calcium carbonate test. E. foraminiferans – abundant in soils.
C.
Which pair of alternatives is highlighted by the life cycle of the cellular slime moulds, such as Dictyostelium?
A. prokaryotic or eukaryotic.
B. plant or animal.
C. unicellular or multicellular.
D. diploid or haploid.
E. autotroph or heterotroph.
C.
Which taxon of eukaryotic organisms is thought to be directly ancestral to the plant kingdom?
A. golden algae.
B. radiolarians.
C. foraminiferans.
D. apicomplexans.
E. green algae.
E.
A biologist discovers an alga that is marine, multicellular, and lives at a depth reached only by blue light. This alga probably belongs to which group?
A. red algae.
B. brown algae.
C. green algae.
D. dinoflagellates.
E. golden algae.
A.
The chloroplasts of all of the following are derived from ancestral red algae, except those of
A. golden algae.
B. diatoms.
C. dinoflagellates.
D. green algae.
E. brown algae.
D.
The chloroplasts of land plants are thought to have been derived according to which evolutionary sequence?
A. cyanobacteria → green algae → land plants.
B. cyanobacteria → green algae → fungi → land plants.
C. red algae → brown algae → green algae → land plants. D. red algae → cyanobacteria → land plants.
E. cyanobacteria → red algae → green algae → land plants.
A.
A snail-like, coiled, porous test (shell) of calcium carbonate is characteristic of which group?
A. diatoms.
B. foraminiferans.
C. radiolarians.
D. gymnamoebas.
E. ciliates.
B.
Diatoms are mostly asexual members of the phytoplankton. Diatoms lack any organelles that might have the 9+2 pattern. They obtain their nutrition from functional chloroplasts, and each diatom is encased within two porous, glasslike valves. Which question would be most important for one interested in the day-to-day survival of individual diatoms?
A. How does carbon dioxide get into these protists with their glass-like valves?
B. How do diatoms get transported from one location on the water’s surface layers
to another location on the surface?
C. How do diatoms with their glasslike valves keep from sinking into poorly lit
waters?
D. How do diatoms with their glasslike valves avoid being shattered by the action
of waves?
E. How do diatom sperm cells locate diatom egg cells?
C.
Thread-like pseudopods that can perform phagocytosis are generally characteristic of which group?
A. radiolarians and forams.
B. gymnamoebas.
C. entamoebas.
D. amoeboid stage of cellular slime moulds.
E. oomycetes.
A.
The Irish potato famine was caused by an organism that belongs to which group?
A. ciliates.
B. oomycetes.
C. diatoms.
D. apicomplexans.
E. dinoflagellates.
B.
You are given an unknown organism to identify. It is unicellular and heterotrophic. It is motile, using many short extensions of the cytoplasm, each featuring the 9+2 filament pattern. It has well-developed organelles and three nuclei, one large and two small. This organism is most likely to be a member of which group?
A. foraminiferans. B. radiolarians. C. ciliates.
D. kinetoplastids. E. slime moulds.
C.
Which of these taxa contains species that produce potent toxins that can cause extensive fish kills, contaminate shellfish, and poison humans?
A. red algae.
B. dinoflagellates. C. diplomonads. D. euglenids.
E. golden algae.
B.
A biologist discovers a new unicellullar organism that possesses more than two flagella and two small, but equal-sized, nuclei. The organism has reduced mitochondria (mitosomes), no chloroplasts, and is anaerobic. To which clade does this organism probably belong?
A. monera.
B. the diplomonads. C. the ciliates.
D. Protista.
E. the euglenids.
B.
According to the endosymbiotic theory of the origin of eukaryotic cells, how did mitochondria originate?
A. from infoldings of the plasma membrane, coupled with mutations of genes for proteins in energy-transfer reactions.
B. from engulfed, originally free-living prokaryotes.
C. by secondary endosymbiosis.
D. from the nuclear envelope folding outward and forming mitochondrial
membranes.
E. when a protoeukaryote engaged in a symbiotic relationship with a protobiont.
B.
Biologists have long been aware that the defunct kingdom Protista is paraphyletic. Which of these statements is both true and consistent with this conclusion?
A. Many species within this kingdom were once classified as monerans.
B. Animals, plants, and fungi arose from different protist ancestors.
C. The eukaryotic condition has evolved only once among the protists, and all
eukaryotes are descendants of that first eukaryotic cell.
D. Chloroplasts among various protists are similar to those found in prokaryotes.
E. Some protists, all animals, and all fungi share a protist common ancestor, but
these protists, animals, and fungi are currently assigned to three different kingdoms.
E.
Protists are alike in that all are A. unicellular.
B. eukaryotic.
C. symbionts.
D. monophyletic.
E. autotrophic.
B.
Which statement about gram-negative bacteria is correct?
A. Penicillins are the best antibiotics to use against them.
B. They often possess an outer membrane containing toxic lipopolysaccharides.
C. Their chromosomes are composed of DNA tightly wrapped around large
amounts of histone proteins.
D. Their cell walls are primarily composed of peptidoglycan. E. None of these are correct.
B.
How can prokaryotes be considered to be more successful on Earth than humans? A. Prokaryotes are much more numerous and have more biomass.
B. Prokaryotes occupy more diverse habitats.
C. Prokaryotes are more diverse in metabolism.
D. Only A and B are correct. E. A, B, and C are correct.
E.
In a hypothetical situation, a bacterium lives on the surface of a leaf, where it obtains nutrition from the leaf’s non-living, waxy covering, while inhibiting the growth of other microbes that are plant pathogens. If this bacterium gains access to the inside of a leaf, it causes a fatal disease in the plant. Once the plant dies, the bacterium and its offspring decompose the plant. What is the correct sequence of ecological roles played by the bacterium in the situation described here? Use only those that apply. 1. Nutrient recycler; 2. Mutualist; 3. Commensal; 4. Parasite; 5. Primary producer.
A. 1, 3, 4. B. 2, 3, 4. C. 2, 4, 1. D. 1, 2, 5. E. 1, 2, 3.
C.
What is the primary ecological role of prokaryotes?
A. parasitizing eukaryotes, thus causing diseases. B. breaking down organic matter.
C. metabolizing materials in extreme environments. D. adding methane to the atmosphere.
E. serving as primary producers in terrestrial environments.
B.
The thermoacidophile, Sulfolobus acidocaldarius lacks peptidoglycan. What is likely to be true of this species? 1. It is a bacterium; 2. It is an archaean; 3. The optimal pH of its enzymes will lie above pH 7; 4. The optimal pH of its enzymes will lie below pH 7; 5. It could inhabit certain hydrothermal springs; 6. It could inhabit alkaline hot springs.
A. 1, 3, and 6. B. 2, 4, and 6. C. 2, 4, and 5. D. 1, 3, and 5. E. 1, 4, and 5.
C.
Assuming that each of these possesses a cell wall, which prokaryotes should be expected to be most strongly resistant to plasmolysis in hypertonic environments?
A. extreme halophiles.
B. extreme thermophiles.
C. methanogens.
D. cyanobacteria.
E. nitrogen-fixing bacteria that live in root nodules.
A.
Which statement about the domain Archaea is false?
A. Genetic prospecting has recently revealed the existence of many previously
unknown archean species.
B. Some archaeans can reduce CO2 to methane.
C. The genomes of archaeans are unique, containing no genes that originated within bacteria.
D. Some archaeans can inhabit solutions that are nearly 30% salt.
E. Some archaeans are adapted to waters with temperatures above the boiling point.
C.
Which of the following are responsible for high levels of O2 in Earth’s atmosphere? A. photoautotrophs.
B. photoheterotrophs.
C. chemoautotrophs.
D. chemoheterotrophs that perform decomposition. E. parasitic chemoheterotrophs.
A.
Match the numbered terms to the descriptions that follow. For each item, choose all appropriate terms, but only appropriate terms. 1. Autotroph; 2. Heterotroph; 3. Phototroph; 4. Chemotroph: An organism that obtains both carbon and energy by ingesting prey
A. 1 only.
B. 4 only.
C. 1 and 3. D. 2 and 4. E. 1, 3, and 4.
D.
Match the numbered terms to the descriptions that follow. For each item, choose all appropriate terms, but only appropriate terms. 1. Autotroph; 2. Heterotroph; 3. Phototroph; 4. Chemotroph: A prokaryote that obtains both energy and carbon as it decomposes dead organisms
A. 1 only.
B. 4 only.
C. 1 and 3. D. 2 and 4. E. 1, 3, and 4.
D.
Match the numbered terms to the descriptions that follow. For each item, choose all appropriate terms, but only appropriate terms. 1. Autotroph; 2. Heterotroph; 3. Phototroph; 4. Chemotroph: An organism that obtains its energy from chemicals
A. 1 only. B. 2 only. C. 3 only. D. 4 only. E. 1 and 4.
D.
Referring to structures found in a gram-positive prokaryotic cell: If this structure connects the cytoplasm of two bacteria, one of these cells may gain new genetic material:
A. endospore. B. sex pilus. C. flagellum. D. cell wall. E. capsule.
B.
Referring to structures found in a gram-positive prokaryotic cell: Not present in all bacteria, this structure enables those that possess it to germinate after exposure to harsh conditions, such as boiling:
A. endospore. B. sex pilus. C. flagellum. D. cell wall.
E. capsule.
A.
Referring to structures found in a gram-positive prokaryotic cell: Not present in all bacteria, this cell covering enables cells that possess it to resist the defences of host organisms:
A. endospore. B. sex pilus. C. flagellum. D. cell wall. E. capsule.
E.
Which statement about the genomes of prokaryotes is correct?
A. Prokaryotic genomes are diploid throughout most of the cell cycle.
B. Prokaryotic chromosomes are sometimes called plasmids.
C. Prokaryotic cells have multiple chromosomes, ʺpackedʺ with a relatively large
amount of protein.
D. The prokaryotic chromosome is not contained within a nucleus but, rather, is
found at the nucleoid region.
E. Prokaryotic genomes are composed of linear DNA (that is, DNA existing in the
form of a line with two ends).
D.
The typical prokaryotic flagellum features
A. an internal 9 + 2 pattern of microtubules.
B. an external covering provided by the plasma membrane.
C. a complex ʺmotorʺ embedded in the cell wall and plasma membrane. D. a basal body that is similar in structure to the cellʹs centrioles.
E. all of these.
C.
Jams, jellies, preserves, honey, and other foodstuffs with a high sugar content hardly ever become contaminated by bacteria, even when the food containers are left open at room temperature. This is because bacteria that encounter such an environment
A. undergo death by plasmolysis.
B. are unable to metabolize the glucose or fructose, and thus starve to death. C. undergo death by lysis.
D. are obligate anaerobes.
E. are unable to swim through these thick and viscous materials.
A.
The predatory bacterium, Bdellovibrio bacteriophorus, drills into a prey bacterium and, once inside, digests it. In an attack upon a gram-negative bacterium that has a slimy cell covering which can inhibit phagocytosis, what is the correct sequence of structures penetrated by B. bacteriophorus on its way to the prey’s cytoplasm? 1. Membrane composed mostly of lipopolysaccharide; 2. Membrane composed mostly of phospholipids; 3. Peptidoglycan; 4. Capsule.
A. 2 → 4 → 3 →1. B. 1 → 3 → 4 → 2. C. 1 → 4 → 3 → 2. D. 4 → 1 → 3 → 2. E. 4 → 3 → 1 → 2.
D.
Which of these is the most common compound in the cell walls of gram-positive bacteria?
A. cellulose.
B. lipopolysaccharide. C. lignin.
D. peptidoglycan.
E. protein.
D.
Though plants, fungi, and prokaryotes all have cell walls, we place them in different taxa. Which of these observations comes closest to explaining the basis for placing these organisms in different taxa, well before relevant data from molecular systematics became available?
A. Some closely resemble animals, which lack cell walls.
B. Their cell walls are composed of very different biochemicals. C. Some have cell walls only for support.
D. Some have cell walls only for protection from herbivores.
E. Some have cell walls only to control osmotic balance.
B.
Concept 6.7 ___(a)___ play key roles in ecological ___(b)___.
(a) Protists
(b) communities
Concept 6.6 ___(a)___ include protists that are closely related to fungi and ___(b)___.
(a) Unikonts
(b) animals
Concept 6.5 Red algae and green algae are the ___(a)___ relatives of land ___(b)___.
(a) closest
(b) plants
Concept 6.4 ___(a)___ are a diverse group of protists defined by DNA ___(b)___.
(a) Rhizarians
(b) similarities
Concept 6.3 ___(a)___ may have originated by ___(b)___ endosymbiosis.
(a) Chromalveolates
(b) secondary
Concept 6.2 ___(a)___ include protists with modified mitochondria and protists with unique ___(b)___.
(a) Excavates
(b) flagella
Concept 6.1 Most ___(a)___ are ___(b)___ organisms.
(a) Eukaryotes
(b) single-celled
