Ch. 28 Homework – Flashcards
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What advantage do organisms that reproduce sexually have over organisms that reproduce asexually?
A. Their offspring can exist in both haploid and diploid stages.
B. Their offspring may be more adaptable to changes in the environment.
C. Their offspring may have more mutations.
D. Their offspring are bigger and better able to reproduce.
answer
B.
Offspring produced by sexual reproduction are genetically different from their parents and may be better able to thrive if the environment changes.
question
Which term describes the fusion of two gametes to form a diploid zygote?
A. Meiosis
B. Mitosis
C. Alternation of generations
D. Syngamy
answer
D.
Syngamy is the fusion of two gametes to form a diploid zygote.
question
Which term describes the multicellular haploid form of a protist that shows alternation of generations?
A. Spore
B. Sporophyte
C. Gametophyte
D. Zygote
answer
C.
A gametophyte is the multicellular haploid form of a protist that shows alternation of generations.
question
Which structure mediates the attachment of spores to a surface on which to grow?
A. Sporophyte
B. Flagella
C. Holdfast
D. Chloroplas
answer
C.
A holdfast attaches spores to surfaces on which they can grow.
question
Which of the following statements about Ulva's haploid stage is true?
A. The haploid Ulva cells are genetically identical to their diploid parents.
B. Haploid cells produce gametes by meiosis.
C. Gametes of the same mating type fuse to produce a diploid zygote.
D. Haploid cells are produced by meiosis of diploid cells.
answer
D.
This statement is true; the diploid sporophyte produces haploid spores through meiosis.
question
How does the haploid form of Ulva "switch" to its diploid form?
A. Sporophytes undergo meiosis to produce spores that germinate into diploid adults.
B. Gametophytes produce cells that undergo meiosis and produce spores that germinate into diploid adults.
C. Sporophytes produce cells that undergo mitosis to produce gametes that fuse to form a zygote.
D. Gametophytes produce cells that undergo mitosis to produce gametes that fuse to form a zygote.
answer
D.
Gametophytes are haploid adults that produce cells that undergo mitosis and form gametes that fuse to form a diploid zygote.
question
True or false? Organisms that exhibit alternation of generations reproduce sexually in the diploid stage.
answer
False.
Organisms that exhibit alternation of generations reproduce asexually in the diploid stage by producing haploid cells that form spores, which then germinate into haploid adults. The haploid adults produce haploid gametes that can then participate in sexual reproduction.
question
The cells of _____ and _____ have modified mitochondria.
A. diplomonads ...parabasalids
B. chlorophytes ... ciliates
C. euglenozoans ... alveolates
D. dinoflagellates ... metazoans
E. fungi ... stramenopiles
answer
A.
The cells of diplomonads and parabasalids have modified or reduced mitochondria.
question
The members of _____ are characterized by cells with small membrane-bounded cavities under their cell membranes.
A. Stramenopila
B. Alveolata
C. Mycetozoa
D. Rhodophyta
E. Chlorophyta
answer
B.
Dinoflagellates, apicomplexans and ciliates are classified in Alveolata, a group characterized by cells with small membrane-bounded cavities under their cell membranes.
question
Golden algae, brown algae, red algae, chlorophytes, and charophyceans are some examples of protists that are _____.
A. decomposers
B. chemoheterotrophic
C. photosynthetic
D. chemoautotrophic
E. photoheterotrophic
answer
C.
All of the listed groups are photosynthetic.
question
Which of these groups consist of parasitic flagellated cells, such as Trypanosoma, the organism that causes sleeping sickness?A. metazoans
B. brown algae
C. ciliates
D. diatoms
E. kinetoplastids
answer
E.
Parasitic flagellated cells, such as Trypanosoma, are classified as kinetoplastids.
question
Which three groups contain large algae known as seaweeds?A. brown algae, red algae, and green algae
B. diatoms, golden algae, and brown algae
C. plants, fungi, and choanoflagellates
D. chlorophytes, charophyceans, and red algae
E. dinoflagellates, apicomplexans, and green algae
answer
A.
All three of these are seaweeds.
question
Stramenopiles include all of the following groups EXCEPT ______.
A. cellular slime molds
B. diatoms
C. brown algae
D. golden algae
E. water molds
answer
A.
Cellular slime molds are amoebozoans
question
Which of these groups is characterized by glasslike walls containing silica?A. brown algae
B. diplomonads
C. plants
D. plasmodial slime molds
E. diatoms
answer
E.
Diatoms are characterized by glasslike walls containing silica.
question
Plasmodium, the parasitic organism that causes malaria, is a _____.
A. ciliate
B. plasmodial slime molds
C. diatom
D. apicomplexan
E. entamoeba
answer
D.
Plasmodium, is an apicomplexan.
question
A paramecium is a(n) _____.
A. apicomplexan
B. ciliate
C. diatom
D. metazoan
E. dinoflagellate
answer
B.
A paramecium makes use of its cilia to move and feed.
question
The largest seaweeds are _____.
A. diatoms
B. dinoflagellates
C. green algae
D. red algae
E. brown algae
answer
E.
Brown algae are the largest of the seaweeds.
question
All of the organisms classified as _____ move and feed using cilia.
A. diatoms
B. apicomplexans
C. dinoflagellates
D. ciliates
E. diplomonads
answer
D.
Ciliates move and feed using cilia.
question
Which group is characterized by cells with fine hairlike projections on their flagella?
A. Alveolata
B. Euglenozoa
C. Metazoa
D. Stramenopila
E. Rhodophyta
answer
D.
Stramenopiles are characterized by cells that bear fine hairlike projections on their flagella.
question
Which of these algal groups possess a photosynthetic pigment that allows them to live in deep water?
A. diatoms
B. green algae
C. metazoans
D. brown algae
E. red algae
answer
E.
The phycobilins and other accessory pigments of red algae allow them to absorb the wavelengths of light that penetrate deep water and to use them in photosynthesis.
question
Which of these groups includes both aquatic decomposers and the parasites responsible for late potato blight?A. red algae
B. diatoms
C. plasmodial slime molds
D. oomycetes
E. plants
answer
D.
Correct. Oomycetes (water molds and their relatives) include both decomposers and the parasites responsible for late potato blight.
question
Which algal group has chloroplasts much like those of green plants in structure and pigment makeup? A. golden algae
B. diatoms
C. red algae
D. chlorophytes
E. brown algae
answer
D.
Chlorophytes (green algae), like green plants, contain both chlorophylls a and b.
question
Which species interaction applies to bees that harvest nectar and pollen from flowers?
A. Mutualism.
B. Competition.
C. Commensalism.
D. Consumption.
answer
A.
Both participants benefit from this interaction: Bees acquire food and flowers are pollinated.
question
Which process is not an example of consumption?
A. Herbivory.
B. Parasitism.
C. Commensalism.
D. Predation.
answer
C. Commensalism is a type of species interaction in which one participant benefits and the other participant is not affected by the interaction.
question
True or false? One example of a coevolutionary arms race is when faster deer evolve and favor wolves and cougars that have stronger eyesight and senses of smell.
answer
True. A coevolutionary arms race involves two species that influence each other's evolution; faster deer favor predators with stronger eyesight and senses of smell to track them.
question
Which form of Plasmodium is the immediate cause of anemia in humans?
A. Diploid zygote.
B. Gametocytes.
C. Merozoites.
D. Sporozoites.
answer
C.
Merozoites are produced in a human liver cell from sporozoites and circulate throughout the bloodstream, infecting and destroying the red blood cells.
question
Which of the following statements about the Plasmodium parasite is true?
A. Merozoites live off the hemoglobin and nutrients in red blood cells and divide to produce more merozoites, destroying red blood cells in the process.
B. The diploid zygote moves from the infected human to the mosquito as part of the mosquito's blood meal.
C. The diploid zygote undergoes meiosis and mitosis to produce haploid merozoites.
D. Plasmodium cells in the mosquito's saliva target red blood cells in a human and produce offspring that infect liver cells.
answer
A.
question
How do humans combat infection by the Plasmodium parasite?
A. Plasmodium cells bind to liver cells that have the CP26 protein on their cell surface and form a complex that is targeted by cytotoxic T cells.
B. Cytotoxic T cells secrete anticoagulant to kill infected red blood cells.
C. Cytotoxic T cells destroy infected liver cells by recognizing a Plasmodium protein bound to an HLA protein on the surface of those cells.
D. Liver cells secrete the HLA-B53 protein, which binds to and inactivates Plasmodium cells in the bloodstream.
answer
C.
Cytotoxic T cells do destroy infected liver cells by recognizing the Plasmodium CP26 protein bound to the HLA-B53 protein on the surface of those cells.
question
Why has the Kingdom Protista been abandoned? (Overview)
A. Some protists are multicellular
B. The Kingdom Protista is paraphyletic.
C. Some protists are more closely related to plants, animals, or fungi than they are to other protists.
D. Some protists are as small as prokaryotes
E. Both of the following are correct: The Kingdom Protista is paraphyletic; Some protists are more closely related to plants, animals, or fungi than they are to other protists.
answer
E.
Recognizing that the Kingdom Protista as originally defined was paraphyletic and that some protists are more closely related to other eukaryotes than to each other, scientists have abandoned the Kingdom Protista and reorganized the entire Domain Eukarya.
question
Which of the following is true of secondary endosymbiosis? (Concept 28.1)
A. An organism containing one endosymbiont engulfs another organism, and that organism becomes an endosymbiont.
B. It is indicated by the presence of a double membrane surrounding the endymbiont.
C. It is indicated by the presence of a nucleomorph.
D. An organism containing an endosymbiont is engulfed by another organism and becomes an endosymbiont.
E. It is indicated by the presence of a mixotroph.
answer
D.
This is a description of secondary endosymbiosis. In many cases secondary endosymbionts are surrounded 4 membranes.
question
Which of the following are two groups that are adapted to anaerobic conditions and contain modified mitochondria that lack DNA? (Concept 28.2)
A. gymnamoebas and slime molds
B. Apicomplexans and forams
C. diplomonads and parabasalids
D. dinoflagellates and diatoms
E. chlorophytes and radiolarians
answer
C.
These groups are known for their modified mitochondria.
question
A sign on the beach states, "Beach Closed. Red Tide." The organisms interfering with your use of this beach are _____. (Concept 28.3)
A. diatoms
B. dinoflagellates
C. species of red algae
D. ciliates
E. amoebas
answer
B.
Dinoflagellate blooms, episodes of explosive population growth, cause red tides in coastal waters.
question
Which supergroup is currently the most controversial in terms of the hypothesis for its origin? (Concept 28.3)
A. The Archaeplastida
B. The rhizaria
C. The Chromalveolates
D. The excavates.
E. The Unikonts
answer
C.
There are a number of conflicting viewpoints regarding the origin of this group, and the DNA evidence is not conclusive. The best current hypothesis is that this group arose by secondary endosymbiosis of a red alga.
question
Many types of foraminiferans form a symbiotic relationship with _______. (Concept 28.4)
A. seaweed
B. algae
C. bacteria
D. fungi
E. amoebas
answer
B.
Forams derive nourishment from photosynthetic algae living within their shells.
question
Archaeplastids, which include red and green algae and land plants, are thought to have descended from a heterotrophic protest that engulfed a(n) ______. (Concept 28.5)
A. Alpha proteobacterium
B. Archaean extremophile
C. Cyanobacterium
D. apicomplexan
E. Slime mold
answer
C. Structural and molecular biological evidence support the idea that endosymbiotic cyanobacteria gave rise to the chloroplasts found in red and green algae and land plants.
question
Which of the following is a correct statement about slime molds? (Concept 28.6)
A. In plasmodial slime molds, the haploid condition is the dominant part of the life cycle.
B. Cellular slime molds form masses when food is scarce, but their cells remain separated.
C. Cytoplasmic streaming helps distribute nutrients and oxygen in cellular slime molds.
D. Cellular slime molds have fruiting bodies that function in sexual reproduction.
E. Cellular slime molds have haploid zygotes.
answer
B.
Cellular slime molds function almost like multicellular organisms when food is depleted. The form a multicellular mass that forms fruiting bodies.
question
_____ are eukaryotic autotrophs that float near the surface of water and are the basis of the food chain. (Concept 28.7)
A. Symbionts
B. Phytoplankton
C. Cyanobacteria
D. Zooplankton
E. Slime molds
answer
B.
These photosynthetic organisms serve as the basis of the food chain.
question
Coral bleaching, which causes high coral mortality, has been occurring widely in coral reefs. Coral bleaching actually refers to the death of symbiotic dinoflagellates living within the corals. Why does coral bleaching cause the corals to die? (Concept 28.7)
A. Dinoflagellates protect the corals from UV radiation.
B. Dinoflagellates provide nutrients from the products of photosynthesis to the corals in exchange for a safe place to live.
C. Dinoflagellates protect the corals from pathogenic bacteria.
D. Dinoflagellates attract zooplankton and other prey that the corals eat.
E. All of the above.
answer
B.
Without the extra nutrients provided by symbiotic protists, the corals cannot compete with other organisms for resources.
question
Which of the following is true of secondary endosymbiosis?
A. It is indicated by the presence of a double membrane surrounding the endymbiont.
B. An organism containing one endosymbiont engulfs another organism, and that organism becomes an endosymbiont.
C. It is indicated by the presence of a nucleomorph.
D. An organism containing an endosymbiont is engulfed by another organism and becomes an endosymbiont.
E. It is indicated by the presence of a mixotroph.
answer
D.
This is a description of secondary endosymbiosis. In many cases secondary endosymbionts are surrounded four membranes.
question
Which group of organisms (ciliates, animals, or plants) has the most complex cells?
A. Plants
B. Animals
C. Ciliates
answer
C.
Single-celled protists are justifiably considered the simplest eukaryotes, but at the cellular level, many protists are very complex. For example, the single cell of a ciliate such as Paramecium is much more complex than any one cell in your body. Read about structural and functional diversity in protists.
