Campbell Biology: Test 2 Study Questions Flashcards

1) Mycoplasmas are bacteria that lack cell walls. On the basis of this structural feature, which statement concerning mycoplasmas should be true?
A) They are gram-negative.
B) They are subject to lysis in hypotonic conditions.
C) They lack a cell membrane as well.
D) They should contain less cellulose than do bacteria that possess cell walls.
E) They possess typical prokaryotic flagella.

2) 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.

Jams, jellies, preserves, honey, and other foodstuffs with 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) experience lysis.
D) are obligate anaerobes.
E) are unable to swim through these thick and viscous materials.

Which two structures play direct roles in permitting bacteria to adhere to each other, or to other surfaces?
1. capsules
2. endospores
3. fimbriae
4. plasmids
5. flagella

A) 1 and 2
B) 1 and 3
C) 2 and 3
D) 3 and 4
E) 3 and 5

Prokaryotic ribosomes differ from those present in eukaryotic cytosol. Because of this, which of the following is correct?
A) Some antibiotics can block protein synthesis in bacteria without effects in the eukaryotic host.
B) Eukaryotes did not evolve from prokaryotes.
C) Translation can occur at the same time as transcription in eukaryotes but not in prokaryotes.
D) Some antibiotics can block the synthesis of peptidoglycan in the walls of bacteria.
E) Prokaryotes are able to use a much greater variety of molecules as food sources than can eukaryotes.

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, "packed" with a relatively large amount of protein.
D) The prokaryotic chromosome is not contained within a nucleus but, rather, is found at the nucleolus.
E) Prokaryotic genomes are composed of circular DNA.

If a bacterium regenerates from an endospore that did not possess any of the plasmids that were contained in its original parent cell, the regenerated bacterium will probably also
A) lack antibiotic-resistant genes.
B) lack a cell wall.
C) lack a chromosome.
D) lack water in its cytoplasm.
E) be unable to survive in its normal environment.

Although not present in all bacteria, this cell covering often enables cells that possess it to resist the defenses of host organisms, especially their phagocytic cells.
A) endospore
B) sex pilus
C) cell wall
D) capsule

Which of the following is an important source of endotoxin in gram-negative species?
A) endospore
B) sex pilus
C) flagellum
D) cell wall
E) capsule

Prokaryotes' essential genetic information is located in the
A) nucleolus.
B) nucleoid.
C) nucleosome.
D) plasmids.
E) exospore.

Match the numbered terms to the description that follows. Choose all 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

Match the numbered terms to the description that follows. Choose all 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

Match the numbered terms to the description that follows. Choose all appropriate terms.
1. autotroph
2. heterotroph
3. phototroph
4. chemotroph
an organism that relies on photons to excite electrons within its membranes
A) 1 only
B) 3 only
C) 1 and 3
D) 2 and 4
E) 1, 3, and 4

Which of the following obtain energy by oxidizing inorganic substancesenergy that is used, in part, to fix CO₂?

A) photoautotrophs
B) photoheterotrophs
C) chemoautotrophs
D) chemoheterotrophs that perform decomposition
E) parasitic chemoheterotrophs

Carl Woese and collaborators identified two major branches of prokaryotic evolution. What was the basis for dividing prokaryotes into two domains?
A) microscopic examination of staining characteristics of the cell wall
B) metabolic characteristics such as the production of methane gas
C) metabolic characteristics such as chemoautotrophy and photosynthesis
D) genetic characteristics such as ribosomal RNA sequences
E) ecological characteristics such as the ability to survive in extreme environments

A hypothetical bacterium swims among human intestinal contents until it finds a suitable location on the intestinal lining. It adheres to the intestinal lining using a feature that also protects it from phagocytes, bacteriophages, and dehydration. Fecal matter from a human in whose intestine this bacterium lives can spread the bacterium, even after being mixed with water and boiled. The bacterium is not susceptible to the penicillin family of antibiotics. It contains no plasmids and relatively little peptidoglycan.

54) Adherence to the intestinal lining by this bacterium is due to its possession of
A) fimbriae.
B) pili.
C) a capsule.
D) a flagellum.
E) a cell wall with an outer lipopolysaccharide membrane.

A hypothetical bacterium swims among human intestinal contents until it finds a suitable location on the intestinal lining. It adheres to the intestinal lining using a feature that also protects it from phagocytes, bacteriophages, and dehydration. Fecal matter from a human in whose intestine this bacterium lives can spread the bacterium, even after being mixed with water and boiled. The bacterium is not susceptible to the penicillin family of antibiotics. It contains no plasmids and relatively little peptidoglycan.

59) This bacterium derives nutrition by digesting human intestinal contents (in other words, food). Thus, this bacterium should be an
A) aerobic chemoheterotroph.
B) aerobic chemoautotroph.
C) anaerobic chemoheterotroph.
D) anaerobic chemoautotroph.

Genetic variation in bacterial populations cannot result from
A) transduction.
B) transformation
C) conjugation
D) mutation.
E) meiosis.

All protists are
A) unicellular.
B) eukaryotic.
C) symbionts.
D) monophyletic.
E) mixotrophic.

An individual mixotroph loses its plastids, yet continues to survive. Which of the following most likely accounts for its continued survival?
A) It relies on photosystems that float freely in its cytosol.
B) It must have gained extra mitochondria when it lost its plastids.
C) It engulfs organic material by phagocytosis or by absorption.
D) It has an endospore.
E) It is protected by a case made of silica.

Which of the following was derived from an ancestral cyanobacterium?
A) chloroplast
B) mitochondrion
C) hydrogenosome
D) mitosome
E) Two of the responses above are correct.

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) cyanobacteria → red algae → green algae → land plants

Which of the following statements about dinoflagellates is true?
A) They possess two flagella.
B) All known varieties are autotrophic.
C) Their walls are usually composed of silica plates.
D) Many types lack mitochondria.
E) Their dead cells accumulate on the seafloor, and are mined to serve as a filtering material.

Which process results in genetic recombination, but is separate from the process by which the population size of Paramecium increases?
A) budding
B) meiotic division
C) mitotic division
D) conjugation
E) binary fission

A large seaweed that floats freely on the surface of deep bodies of water would be expected to lack which of the following?
A) thalli
B) bladders
C) holdfasts
D) gel-forming polysaccharides

Green algae differ from land plants in that many green algae
A) are heterotrophs.
B) are unicellular.
C) have plastids.
D) have alternation of generations.
E) have cell walls containing cellulose.

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 proteobacteria
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 protocell

Which protists are in the same eukaryotic supergroup as land plants?
A) green algae
B) dinoflagellates
C) red algae
D) brown algae
E) both green algae and red algae

The structural integrity of bacteria is to peptidoglycan as the structural integrity of plant spores is to
A) lignin.
B) cellulose.
C) secondary compounds.
D) sporopollenin.

All of the following are common to both charophytes and land plants except
A) sporopollenin.
B) lignin.
C) chlorophyll a.
D) cellulose.
E) chlorophyll b.

The following are all adaptations to life on land except
A) rings of cellulose-synthesizing complexes.
B) cuticles.
C) tracheids.
D) reduced gametophyte generation.
E) seeds.

Which of the following is true of the life cycle of mosses?
A) The haploid generation grows on the sporophyte generation.
B) Spores are primarily distributed by water currents.
C) Antheridia and archegonia are produced by gametophytes.
D) The sporophyte generation is dominant.
E) The growing embryo gives rise to the gametophyte.

In which of the following taxa does the mature sporophyte depend completely on the gametophyte for nutrition?
A) Pterophyta
B) Bryophyta
C) horsetail (Equisetum)
D) Pterophyta, Bryophyta, and horsetail (Equisetum)
E) Pterophyta and Bryophyta

Which of the following is not evidence that charophytes are the closest algal relatives of plants?
A) similar sperm structure
B) the presence of chloroplasts
C) similarities in cell wall formation during cell division
D) genetic similarities in chloroplasts
E) similarities in proteins that synthesize cellulose

Which of the following is a land plant that has flagellated sperm and a sporophyte-dominated life cycle?
A) fern
B) moss
C) liverwort
D) charophyte
E) hornwort

What is the most important function of the seed coat?

A) Protection from temperature

B) Protection from water

C) Protection from physical damage

D) Keeps embryo dormancy

E) All of the above

In addition to seeds, which of the following characteristics are unique to the seed-producing plants?
A) sporopollenin
B) lignin present in cell walls
C) pollen
D) use of air currents as a dispersal agent
E) megaphylls

Gymnosperms differ from both extinct and extant (living) ferns because they
A) are woody.
B) have macrophylls.
C) have pollen.
D) have sporophylls.
E) have spores.

Which of the following statements correctly describes a portion of the pine life cycle?
A) Female gametophytes use mitosis to produce eggs.
B) Seeds are produced in pollen-producing cones.
C) Pollen grains contain female gametophytes.
D) A pollen tube slowly digests its way through the triploid endosperm.

Which of the following statements is true of the pine life cycle?
A) Cones are homologous to the capsules of moss plants.
B) The pine tree is a gametophyte.
C) Male and female gametophytes are in close proximity during gamete synthesis.
D) Conifer pollen grains contain male gametophytes.
E) Double fertilization is a relatively common phenomenon.

Which trait(s) is (are) shared by many modern gymnosperms and angiosperms?

1. pollen transported by wind
2. lignified xylem
3. microscopic gametophytes
4. sterile sporophylls, modified to attract pollinators
5. endosperm

A) 1 only
B) 1 and 3
C) 1, 2, and 3
D) 1, 3, and 5
E) 2, 4, and 5

What is true of stamens, sepals, petals, carpels, and pinecone scales?
A) They are female reproductive parts.
B) None are capable of photosynthesis.
C) They are modified leaves.
D) They are found on flowers.
E) They are found on angiosperms.

Which of the following are structures of angiosperm gametophytes?
A) immature ovules
B) pollen tubes
C) ovaries
D) stamens
E) sepals

Which of the following is a characteristic of all angiosperms?
A) complete reliance on wind as the pollinating agent
B) double internal fertilization
C) free-living gametophytes
D) carpels that contain microsporangia
E) ovules that are not contained within ovaries

Carpels and stamens are
A) sporophyte plants in their own right.
B) gametophyte plants in their own right.
C) gametes.
D) spores.
E) modified sporophylls.

Which of the following flower parts develops into a seed?
A) ovule
B) ovary
C) fruit
D) stamen

Which of the following flower parts develops into the pulp of a fleshy fruit?
A) stigma
B) style
C) ovule
D) ovary
E) micropyle

Angiosperms are the most successful terrestrial plants. Which of the following features is unique to them and helps account for their success?
A) wind pollination
B) dominant gametophytes
C) fruits enclosing seeds
D) embryos enclosed within seed coats
E) sperm cells without flagella

What is the greatest threat to plant diversity?
A) insects
B) grazing and browsing by animals
C) pathogenic fungi
D) competition with other plants
E) human population growth