Chapter 28 Quiz; Protists
Which organisms are capable of producing a "red tide"? - Dinoflagellates - None of the listed responses is correct. - Euglenids - Sporozoans - Chrysophytes (diatoms)
Dinoflagellates
Which example below is a characteristic shared by diplomonads and parabasalids? - Both lack plastids. - Both have two nuclei. - Both have a single flagellum. - Both lack mitochondria. - Both are adapted to aerobic environments.
Both lack plastids.
Which of the following is not a protist genera that parasitizes humans? - Chlamydomonas - All of the listed genera consist of human parasites. - Entamoeba - Trichomonas - Plasmodium
Chlamydomonas
Which of these groups includes photosynthetic unicellular organisms with flagella and contractile vacuoles? - Euglenids - Apicomplexans - Ciliates - Dinoflagellates - Diatoms
Euglenids
Which of the following is one of the main weaknesses of the proposed classification scheme in which all eukaryotes are divided into four supergroups? - It shows all four supergroups diverging simultaneously from a common ancestor. - It postulates that photosynthetic protists arose by way of endosymbiosis. - It does not explain the extra membranes found in some plastids. - It does not take into account the importance of endosymbiosis. - It does not account for "amitochondriate" protists.
It shows all four supergroups diverging simultaneously from a common ancestor.
Which of the following is the best description of protists' contribution to photosynthesis? - About 30% of the world's photosynthesis is performed by protists. - The net effect of protists is to impede photosynthesis by parasitizing plants. - Only terrestrial protists substantially contribute to photosynthesis. - Protists carry out the majority of the world's photosynthesis. - Protists play an important role only through symbioses with photosynthetic organisms.
About 30% of the world's photosynthesis is performed by protists.
Which of the following is not a group included in the protists? - All of the listed groups are protists. - Forams - Diatoms - Brown algae - Ciliates
All of the listed groups are protists.
Which of the following is not a structure used for locomotion in protists? - All of the listed structures are used for locomotion in protists. - Undulating membrane - Pseudopodia - Flagella - Cilia
All of the listed structures are used for locomotion in protists.
What do a carnivorous dinoflagellate, a parasitic apicomplexan, and a ciliate have in common?
All three have sacs known as alveoli just beneath their plasma membranes.
Which of these groups includes parasitic unicellular organisms with a complex of organelles specialized for penetrating host cells and tissues? - Apicomplexans - Ciliates - Euglenoids - Dinoflagellates - Diatoms
Apicomplexans
Which protist group is thought to be most closely related to animals? - Choanoflagellates - Alveolates - Stramenopiles - Euglenozoans - Diplomonads
Choanoflagellates
Which of these groups is characterized by cells that have more than one nucleus? - Ciliates - Apicomplexans - Euglenids - Dinoflagellates - Diatoms
Ciliates
Which of these groups includes unicellular organisms that, due to the structure of their cell walls, can withstand pressures equal to the pressure under each leg of a table supporting an elephant? - Diatoms - Apicomplexans - Ciliates - Euglenids - Dinoflagellates
Diatoms
Which of these groups includes species that produce a substance that is toxic to humans? - Dinoflagellates - Apicomplexans - Ciliates - Euglenids - Diatoms
Dinoflagellates
Protists are best described as which of the following? - Eukaryotes that are not plants, animals, or fungi - Single-celled organisms that are not bacteria - The domain containing the greatest range of unicellular structures and metabolisms - Simple eukaryotes lacking a well-developed cytoskeleton - The most diverse group of prokaryotic organisms
Eukaryotes that are not plants, animals, or fungi
Parasites of the genus Trypanosoma evade immune responses through what defense? - Frequently changing their surface proteins - Causing little damage to the host - Infecting cells of the immune system - Forming dormant endospores - Remaining on the outside of the host
Frequently changing their surface proteins
Why have protists been "mixed in" with plants, animals, and fungi under the hypothesis that groups eukaryotes into five supergroups?
Many protists are more closely related to plants, animals, or fungi than they are to each other and recent evidence makes it clear that the former kingdom Protista was paraphyletic.
Which protists were once categorized as fungi due to their multinucleate filaments that resemble hyphae? - Oomycetes - Parabasalids - Golden algae - Stramenopiles - Dinoflagellates
Oomycetes
__________ is a protist that causes late blight of potatoes and was responsible for the Irish potato famine of the 19th century.
Phytophthora infestans
Which of the following does not take place during the process of conjugation? - Reproduction - Exchange of genetic material - Cell fusion - Mitosis - Meiosis
Reproduction
Which of the following is not a cellular organelle possessed by a protist? - Sporozoite - Mitochondria - Plastid - Hydrogenosome - Mitosome
Sporozoite
What is one way in which a cellular slime mold differs from a plasmodial slime mold?
What is one way in which a cellular slime mold differs from a plasmodial slime mold?
The holdfast of brown algae functions in __________.
anchoring the algae
Green algae are divided into two main groups, the charophytes and the __________.
chlorophytes
The term mixotroph indicates that a protist __________.
combines photosynthesis and heterotrophic nutrition
Molecular data suggest that plastids originated as __________ engulfed by a heterotrophic eukaryote.
cyanobacteria
Although controversial, chromalveolates are proposed as a clade whose common ancestor __________.
engulfed a photosynthetic red alga in a secondary endosymbiosis event
Organisms are classified as Excavata based on __________.
morphological studies of the cytoskeleton
The term algae refers to __________.
several diverse groups of photosynthetic protists
Apicomplexans are currently assigned to the chromalveolates because __________.
the apicoplast, a modified plastid, appears to be of red algal origin
