Campbell Mastering Biology Chapter 28 Questions
-Many protists are more closely related to plants, animals, or fungi than they are to each other.
-Recent evidence makes it clear that the former kingdom Protista was paraphyletic.
(Both the first and third answers are correct)
Why have protists been "mixed in" with plants, animals, and fungi under the hypothesis that groups eukaryotes into five supergroups?
various pieces of evidence indicate that the kingdom Protista cannot be monophyletic
The placement of all protists in one kingdom caused dissatisfaction among taxonomists mainly because _____.
It shows all five supergroups diverging simultaneously from a common ancestor.
Which of the following is one of the main weaknesses of the proposed classification scheme in which all eukaryotes are divided into five supergroups?
morphological studies of the cytoskeleton
Organisms are classified as Excavata based on _____.
Both lack plastids.
Which example below is a characteristic shared by diplomonads and parabasalids?
The molecular composition of their surface changes continually.
How do trypanosomes withstand the attack of a host's immune system?
Which of these groups includes photosynthetic unicellular organisms with flagella and contractile vacuoles?
engulfed a photosynthetic red algae in a secondary endosymbiosis event
Although controversial, chromalveolates are proposed as a clade whose common ancestor _____.
the apicoplast, a modified plastid, appears to be of red algal origin
Apicomplexans are currently assigned to the chromalveolates because _____.
In many types of protist life cycles, the union of two gametes that results in a diploid zygote is called _____.
All three have sacs known as alveoli just beneath their plasma membranes.
What do a carnivorous dinoflagellate, a parasitic apicomplexan, and a ciliate have in common?
Which organisms are capable of producing a "red tide"?
Which of these groups includes species that produce a substance that is toxic to humans?
Which of these groups includes parasitic unicellular organisms with a complex of organelles specialized for penetrating host cells and tissues?
Which of these groups is characterized by cells that have more than one nucleus?
How do ciliates generate genetic variation?
Which protists were once categorized as fungi due to their multinucleate filaments that resemble hyphae?
_____ is a protist that causes late blight of potatoes and was responsible for the Irish potato famine of the 19th century.
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?
-All are autotrophs.
-They all have flagella with numerous fine, hairlike projections.
-All are stramenopiles.
-All of the listed responses are correct.
(all of them are correct)
Which characteristic is shared by most diatoms, golden algae, and brown algae at least at some stage of their life cycles?
The general term given to a plantlike body that lacks true stems, leaves, and roots and that shows little tissue differentiation is _____.
What is the purpose of the "floats" in some brown algae?
Which of the following organisms is commercially harvested to extract algin from their cell walls?
During a bloom, diatom populations may increase rapidly. If many diatoms die and sink to the bottom without being eaten, they effectively pump carbon dioxide out of the atmosphere.
What role do diatoms play in the global carbon balance affecting global warming?
the tests of dead radiolarians
On some areas of the seafloor, one could observe an "ooze" that is hundreds of meters thick. What creates this ooze?
their photosynthetic pigments efficiently absorb blue and green light
Many species of red algae are adapted to deeper water due to the fact that _____.
especially diverse life cycles
The red algae are characterized by _____.
Which of the following groups of algae is/are most closely related to land plants?
The plasmodium is undivided by membranes and contains many diploid nuclei; therefore, it is not technically multicellular.
In lab class, a plasmodial slime mold is used as a demonstration organism. One of the students does not understand why this organism is not considered multicellular. How would you explain it to her?
None of the listed responses is correct.
To which supergroup do amoebas belong?
It is estimated that protists perform up to what percentage of the world's photosynthesis?
Hypermastigotes are important endosymbionts that live in the guts of _____.