Protozoans Flashcards
Cilia and flagella are similar in _____
their internal structure
The sliding microtubule hypothesis explains
ciliary and flagellar action
Most of the amebas reproduce by
binary fission
A resistant, quiescent stage in the life cycle of a protozoan is called a
cyst
The agents of red tide, which may be red, brown, yellow, or colorless, are the ___
dinoflagellates
African sleeping sickness and Chagas’s disease are both caused by protozoa in the genus _____
Trypanasoma
Mental retardation of a child can be caused by infection of its mother by the protistan _____ during the child’s fetal development. This may be the simple result of the mother changing a cat litter box while pregnant
Toxoplasma
The agent of malaria, which kills one million people each year globally, is the protistan _______
Plasmodium
Some amebas make a protective shell or test. Those that construct this shell of calcium carbonate are the ______
foraminiferans
Amebas that construct their shell or test of siliceous material, and are also found in marine waters are the ______
radiolarians
While many amebas are heterotrophic, a few are endoparasites. The agent of amoebic dysentery is the protistan _____
Entamoeba histolytica.
All members of phylum Apicomplexa share two features, which are ____ and _____
an apical complex; endoparasitism.
Which of the following disease agents does a vector mosquito transmit?
the protistan Plasmodium vivax.
The members of phylum Ciliophora usually have cilia but the one trait that characterizes them is being _____
multinucleate
The members of phylum Ciliophora have complex reproductive cycles, but they usually include ____ and ____
asexual binary fission: conjugation.
Which of the following is not a form of asexual reproduction used by protists?
conjugation
The infective stage in the life cycle of a sporozoan is the ___
oocyst
When cilia are fused into a sheet of material that can be used for locomotion or for moving food particles toward the cytopharynx, the sheet is called a(n) ____
undulating membrane.
Another term for the joining of two gametes is _____
syngamy
Some ciliates have cilia fused to form stiffened tufts called _______
cirri
Unlike most of the other kinds of protists, the __________ exist in a diploid state most of the life cycle and meiosis precedes syngamy.
ciliates
When a person becomes infected with the protist Plasmodium, sporozoites enter the liver cells and undergo a process known as _________, producing merozoites which then enter red blood cells.
schizogony
Some of the oldest known fossils of eukaryotic organisms that have been identified are members of the group called _____
radiolarians
Movement by pseudopodia is used by a variety of protozoa including amebas.
true
The arrangement of microtubules within a flagella is similar to the internal structure of another organelle, the mitochondrion.
false
Contractile vacuoles are mainly functional in regulating water within the cell, and are most active in freshwater protozoans.
true
Respiration exchanges in protists occur via specialized membranous organelles.
false
Lobopodia are large and blunt, contain both endoplasm and ectoplasm.
true
Zygotic meiosis is meiosis that occurs after fertilization such as in Apicomplexa.
true
Intermediary meiosis is meiosis that occurs between haploid and diploid generations such as in foraminiferans.
true
Conjugation is when gametic nuclei are exchanged between individuals such as inPlasmodium.
false
It is believed that the green algae gave rise to multicellular plants.
true
Undulipodia is the term that has been given to the various types of pseudopodia.
false
One difference between pseudopodia and flagella and cilia is that pseudopodia are bound by the cell membrane, whereas flagella and cilia are naked extensions of microtubules.
false
Multiple fission is common in the apicomplexans and some amebas, and is also known as schizogony.
true
The amebas, Plasmodium, Paramecium, and Euglena all belong to different phyla.
true
Many species of foraminiferans live in a close symbiotic relationship with stony corals, and are very important in the formation and maintenance of coral reefs.
false
Toxoplasmosis typically does not cause disease symptoms in healthy humans, but may pose a threat to HIV-infected persons, the elderly, and pregnant women.
true
The protozoans are characterized by the _____ grade of organization.
protoplasmic
The protozoans acquire energy using the _______
mitochondria
Locomotion using _____ involves transforming cytoplasm between the sol to gel states.
pseudopodia
Protozoans that ingest visible food particles are referred to as _____ feeders.
phagotrophic
Specialized structures called ____ maintain osmotic balance in most protozoans.
contractile vacuoles
