Protists And Fungi Flashcards
1
Q
What are the three groups of protists based on locomotion?
A
Ciliates, flagellates, and amoebas.
2
Q
How do ciliate protists move?
A
By waving large numbers of small, hair-like cilia to propel themselves through water.
3
Q
How do flagellate protists move?
A
By whipping or rotating one or more long flagella.
4
Q
How do amoeboid protists move?
A
Using pseudopods.
5
Q
Are all protists actively motile?
A
No, not all protists are actively motile.
6
Q
What is an example of a sessile protist?
A
Most diatoms are sessile.
7
Q
What are the three types of nutrition in protists?
A
Protists can be autotrophic, heterotrophic, or saprotrophic.
8
Q
How do autotrophic protists generate energy?
A
Autotrophic protists have chloroplasts to generate energy through photosynthesis.
9
Q
What is the feeding method of heterotrophic protists?
A
Heterotrophic species feed on organic materials, often ingesting their food through phagocytosis.
10
Q
What occurs during phagocytosis?
A
In phagocytosis, a food particle is engulfed by the cell by pinching off a small amount of plasma membrane, forming a food vacuole called a phagosome.
11
Q
What role do lysosomes play in phagocytosis?
A
A lysosome fuses with the phagosome to digest the food using hydrolytic enzymes.
12
Q
What are saprobes?
A
Saprobes are organisms that feed on dead organisms or organic waste products.
13
Q
What are mixotrophs?
A
Mixotrophs switch between autotrophic and heterotrophic metabolisms, depending on the availability of environmental resources.
14
Q
What are the common modes of asexual reproduction in protists?
A
Most protists reproduce asexually through binary fission, multiple fission, or budding.
15
Q
What is binary fission?
A
Binary fission is the most common mode of reproduction and results in two identical daughter cells.
16
Q
What is multiple fission?
A
Multiple fission, or schizogony, involves several nuclear divisions before the cells divide, leading to the production of spores or sporozoites.
17
Q
What is budding in protists?
A
In budding, a parent cell produces a small offspring that later grows to reach its adult size.
18
Q
Is sexual reproduction common among protists?
A
Yes, sexual reproduction is also common among protists, allowing for genetic recombination.
19
Q
Can protists switch between asexual and sexual reproduction?
A
Many species can switch between asexual and sexual reproduction.
20
Q
What can accompany sexual reproduction in protists?
A
Sexual reproduction can be accompanied by the production of cysts that protect the organism from extreme temperatures or pH conditions.
21
Q
Do protists have embryologic development?
A
Protists lack any sort of embryologic development.
22
Q
How are gametes produced in ciliates, flagellates, and amoebas?
A
In ciliates, some flagellates, and amoebas, gametes are produced through meiosis.
23
Q
When do meiotic divisions occur in apicomplexans?
A
In apicomplexans, meiotic divisions occur after fertilization.
24
Q
What is the life cycle strategy of some amoebas?
A
Some amoebas alternate between haploid and diploid life stages, leading to alternation of generations, a strategy also seen in plants.
25
What is the method of sexual reproduction in ciliates like Paramecium?
Ciliates reproduce sexually through conjugation.
26
What happens during conjugation in ciliates?
Two different mating types join by a cytoplasmic bridge.
27
What occurs to the diploid micronuclei during conjugation?
The diploid micronuclei undergo meiosis producing four daughter nuclei, three of which degrade.
28
What follows meiosis in the process of conjugation?
Mitosis occurs after meiosis.
29
What do the cells do with the resulting nuclei after mitosis?
Each cell transfers one of the two resulting nuclei to the other cell.
30
What happens to the original macronucleus during conjugation?
The original macronucleus disintegrates.
31
What is reconstructed after the transfer of nuclei in conjugation?
The micronucleus and macronucleus are reconstructed, incorporating the new DNA.
32
What is Excavata?
Excavata is a group of unicellular and asymmetrical species with a shallow groove on one side for feeding. Some are predators or parasites while others are photosynthetic.
33
What are diplomonads?
Diplomonads are anaerobic organisms that acquire energy through glycolysis or other pathways.
## Footnote
An example is giardia, a non-life-threatening intestinal parasite that causes diarrhea in many animal species.
34
What are parabasalids?
Parabasalids can colonize the guts of ruminant animals and termites as they can digest cellulose.
## Footnote
The parabasalid Trichomonas causes trichomoniasis, a sexually transmitted disease that causes vaginitis in females but is asymptomatic in males.
35
What are euglenozoans?
Euglenozoans are a diverse group of autotrophs, heterotrophs, mixotrophs, and parasites.
## Footnote
This group includes Leishmania, which is transmitted by sandflies and prominently affects dogs in the Eastern United States. Cutaneous leishmaniasis can cause skin sores and visceral leishmaniasis affects internal organs.
36
What organisms are included in the stramenopiles?
The stramenopiles include brown algae, yellow algae, and diatoms.
37
How many flagella do flagellated stramenopiles have?
Flagellated stramenopiles have two flagella, one short and smooth and one long and hairy.
38
Are all stramenopiles photosynthetic?
Some stramenopiles are photosynthetic, with chloroplasts derived from red algae, while others are heterotrophic.
39
What characterizes the alveolates?
The alveolates are characterized by the presence of alveoli, which are membrane-bound sacs located beneath the cell membrane.
40
What is Plasmodium?
Plasmodium is a parasite transmitted by mosquitoes that causes malaria, responsible for around half a million deaths per year, mostly in children.
41
What is Toxoplasma?
Toxoplasma is an intestinal parasite of cats and other animals that can cause severe birth defects if a pregnant woman is infected.
42
What are dinoflagellates?
Dinoflagellates are primary producers in coral reefs and aquatic systems, known for causing harmful 'red tides' during population explosions.
43
What are ciliates?
Ciliates are a diverse group of microorganisms with rows of cilia used for feeding. They have two nuclei: a micronucleus for sexual reproduction and a macronucleus for non-reproductive functions.
44
Can ciliates be pathogenic?
It is rare for ciliates to be pathogenic; many are free-living or symbiotic within animals.
45
What are Rhizaria?
Rhizaria are a group of mostly marine amoebas with many long, slender pseudopods.
46
What is a pseudopod?
A pseudopod is a temporary extension of the cell that many microorganisms use to move or feed.
47
What do many members of Rhizaria produce?
Many members produce tests, beautiful, snowflake-like shells made of calcium carbonate or silica.
48
What happens to rhizarians after they die?
After rhizarians die, their tests sink to form thick layers of sediment hundreds of meters deep.
49
How do Rhizaria affect the carbon cycle?
This process reduces the amount of carbon dioxide in the atmosphere by storing it deep in the ocean floor.
50
What do tests made millions of years ago form?
Tests made millions of years ago form today's limestone, chalk, and chert.
51
What is Amoebozoa?
Amoebozoa is a diverse group of naked and testate, or shelled, amoebas.
52
What are the characteristics of Amoebozoa?
Some species have large, multinucleated cells and some have multicellular stages.
53
How do amoebas move?
Amoebas move by extending their slender pseudopods and shifting their cytoplasm in the direction of movement.
54
What is an infamous member of the Amoebozoa group?
Acanthamoeba castellani, which can seriously damage the cornea of the eye.
55
Where can Acanthamoeba castellani be found?
It can be found on unsanitized contact lenses.
56
What do slime molds share similarities with?
Slime molds share many similarities to fungi due to convergent evolution.
57
What is Entamoeba histolytica?
Entamoeba histolytica is an amoeba that can affect humans, other primates, dogs, and cats.
58
How do infections from Entamoeba histolytica occur?
Infections occur by ingesting contaminated water.
59
Where do infections from Entamoeba histolytica mainly happen?
These infections mainly happen in tropical areas.
60
What is Archaeplastida?
Archaeplastida is a superkingdom that includes plants and their closest relatives: glaucophytes, red algae, and green algae.
61
What types of organisms are found in Archaeplastida?
Organisms in Archaeplastida can be unicellular, multicellular, or colonial.
62
What is the range of life cycles in Archaeplastida?
The life cycles of protists in Archaeplastida range from simple to complex.
63
What are Opisthokonta?
Opisthokonta is a group that includes animals, fungi, and their closest relatives, which are groups of protists.
64
What are microsporidians?
Microsporidians are parasitic fungi that infect insects, crustaceans, and fish.
65
Are microsporidians considered true fungi?
Microsporidians are sometimes considered true fungi and sometimes a sister group.
66
What other organisms fall into the Opisthokonta grouping?
Amoebas and flagellates also fall into the Opisthokonta grouping.
67
What is Giardia?
Giardia is a flagellated protozoa that infects many patients, though not all show symptoms.
68
What role do veterinary technicians play in diagnosing Giardia?
Veterinary technicians play an active role in the tests needed for diagnosis, whether that's processing the sample for an outside laboratory to assess or microscopically analyzing the sample themselves.
69
What are zooxanthellae?
Zooxanthellae are photosynthetic dinoflagellates that live in mutualistic relationships with corals.
70
What do corals provide to zooxanthellae?
Corals protect zooxanthellae and provide compounds required for photosynthesis.
71
What happens to reef-building corals without zooxanthellae?
They lose their pigment, a process called bleaching, and die.
72
What role do parabasalids play in termite guts?
Parabasalids aid in the digestion of cellulose, a component of wood.
73
What is the role of fungi-like saprobes?
They are important decomposers that turn over organic matter to enrich soil and water with inorganic nutrients.
74
What are some diseases caused by protists?
Protists cause malaria, leishmaniasis, and toxoplasmosis.
75
What pathogen causes potato blight?
The water mold Phytophthora infestans causes potato blight.
## Footnote
Potato blight led to the Irish potato famine and killed about one million people.
76
What types of mildew can protists cause?
Protists can cause downy and powdery mildew in a wide variety of fruits and vegetables.
77
What is an important protist pathogen of humans?
An important protist pathogen of humans is Plasmodium, a genus of apicomplexans that causes malaria.
78
How many disease-related deaths does malaria cause in the tropics annually?
Malaria is responsible for around half a million disease-related deaths per year in the tropics.
79
Which species of Plasmodium is most common in humans?
P. falciparum is the most common species that infects humans.
80
How is P. falciparum transmitted to humans?
P. falciparum is largely transmitted to humans by the mosquito Anopheles gambiae.
81
What are sporozoites in the context of malaria?
Sporozoites are transmitted from mosquitos to humans, where they become schizonts and release merozoites.
82
How do parasites reproduce in red blood cells?
Parasites asexually reproduce in red blood cells and some undergo sexual reproduction as well.
83
What happens to gametes ingested by a mosquito?
Gametes ingested by a mosquito form zygotes and sporozoites.
84
What was unknown about malaria until about 100 years ago?
People didn't know malaria was caused by a protist or that it was transmitted by Anopheles mosquitoes.
85
What does the term 'malaria' mean?
'Malaria' means 'bad air' due to its mysterious transmission.
86
What efforts were made to control malaria in the United States?
Extensive efforts in controlling mosquitoes with DDT, an insecticide, eradicated the disease.
87
What are microsporidians?
Microsporidians are a group of obligate intracellular parasites of animals, frequently insects.
88
Do microsporidians have mitochondria?
Microsporidians lack mitochondria but retain some mitochondrial genes in their genome.
89
Who do microsporidians typically affect?
Microsporidians typically only cause disease in immunocompromised individuals.
90
What is Encephalitozoon cuniculi?
Encephalitozoon cuniculi is a microsporidian that infects the brain and kidneys and may cause neurodegenerative disease.
91
How common is Encephalitozoon cuniculi in humans?
The parasite is rare in humans but common in rabbits.
92
How can Encephalitozoon cuniculi be transmitted?
It may be transmitted zoonotically through spores in the urine.
93
What are Blastocladiomycetes, Neocallismastigomycetes, and Chytridiomycetes?
They are related groups of fungi that share the ancestral trait of motile, flagellated zoospores.
94
What impact have some chytrids had on amphibians?
Some chytrids have been linked to mass die-offs of amphibians.
95
What role do Neocallismastigomycetes play in digestion?
They obtained cellulases from bacteria, which digest cellulose and lignin.
96
Where can Neocallismastigomycetes be found?
They can be found in the stomachs of animals including sheep, kangaroos, and elephants.
97
What are cellulases?
Cellulases are enzymes that digest cellulose and lignin.
98
What are Glomeromycetes?
Glomeromycetes are a small group of asexual plant symbionts that form mutualisms with many species of trees and herbaceous plants.
99
What type of mycorrhizae do most Glomeromycetes form?
Most glomeromycetes form arbuscular mycorrhizae.
100
What is the relationship between Glomeromycetes and plants?
Fungal hyphae associate with plant roots and exchange nutrients, with the plants providing the fungus with carbon and the fungus providing the plant with minerals from the soil.
101
What are the Dikarya?
The Dikarya, or higher fungi, are a large group containing morels, truffles, mushrooms, toadstools, rusts, and shelf fungi.
102
What are Basidiomycetes named for?
Basidiomycetes are named for their reproductive structures, basidia, found in the gills of their spore-forming fruiting body, recognized as the mushroom.
103
What is a key characteristic of Ascomycetes?
The ascomycetes have a similar life cycle to Basidiomycetes, although many are asexual, including the single-celled yeasts.
104
What structures do fungal cells contain?
Fungal cells contain mitochondria, complex systems of internal membranes, and a membrane-bound nucleus.
105
How is the DNA of fungi organized?
The DNA of fungi is organized and compacted by being wrapped around histones, and some fungi also possess accessory genomic structures analogous to bacterial plasmids.
106
What is the composition of fungal cell walls?
Fungal cell walls contain chitin, a complex polysaccharide also present in the exoskeletons of insects and other arthropods.
107
What are hyphae?
Hyphae are filaments that branch and form a network called the mycelium in multicellular fungi.
108
What is the thallus in fungi?
The thallus is the undifferentiated, non-vascular tissue in fungi and other organisms.
109
What are septa?
Septa are porous cross-walls that separate individual hyphae and allow the continuous flow of cytoplasm between cells.
110
What type of hyphae do bread molds have?
Bread molds have coenocytic hyphae, which are not separated by septa and form large, multinucleated cells.
111
How do yeasts differ from multicellular fungi?
Yeasts are unicellular and do not have hyphae or a mycelium.
112
What type of organisms are fungi typically classified as?
Fungi are typically saprobes, also called saprophytes, obtaining nutrients from dead or decaying organic material.
113
What metabolic capabilities do fungi possess?
Fungi possess a wide variety of metabolic pathways that can break down difficult-to-process materials, like cellulose or lignin in wood.
114
What is a unique ability of some fungi in bioremediation?
Some fungi are able to break down jet fuel, making them useful agents in bioremediation.
115
How do fungi reproduce?
Many fungi reproduce both sexually and asexually.
116
What do both types of reproduction in fungi produce?
Both types of reproduction can produce spores, which are capable of dispersing great distances through the wind or carried by other organisms.
117
What are the methods of asexual reproduction in fungi?
Asexual reproduction of fungi includes fragmentation, budding, and spore production.
118
What are the three stages of sexual reproduction in fungi?
The three stages of sexual reproduction in fungi are plasmogamy, karyogamy, and meiosis.
119
What is plasmogamy?
Plasmogamy is the process of two cells fusing to bring together two haploid nuclei, producing a dikaryote.
120
What can happen during plasmogamy in basidiomycetes?
This stage can be very long for basidiomycetes, forming a secondary mycelium and the basidiocarp, which is the fruiting body or mushroom.
121
What is karyogamy?
Karyogamy is the process of two haploid nuclei fusing to form a diploid nucleus with two sets of chromosomes.
122
What does meiosis produce in fungi?
Meiosis then produces haploid nuclei, which are often incorporated into spores.
123
How does plasmogamy occur in fungi?
Plasmogamy can take place through several mechanisms.
124
What are gametangia?
In some fungi, specialized sex organs called gametangia produce and release gametes.
125
How do gametangia interact in some fungi?
In other fungi, gametangia contact each other, and nuclei from the male are donated to the female.
126
What happens when gametangia fuse?
In other fungi, gametangia fuse to bring haploid nuclei together.
127
How do some fungi reproduce without gametangia?
Other fungi have no gametangia. In these organisms, hyphae contact each other, fuse, and exchange nuclei.
128
What is the process of sexual reproduction in ascomycetes?
Sexual reproduction occurs within asci formed by the fusion of an ascogonium and antheridium, developing into a saclike ascocarp, the fruiting body.
129
What happens to the nuclei in a dikaryotic ascus?
The nuclei fuse, forming a diploid zygote.
130
What processes does the diploid zygote undergo?
The zygote goes through meiosis, mitosis, and cell division to form ascospores.
131
What is involved in asexual reproduction in ascomycetes?
Asexual reproduction involves conidiophores, which are modified hyphae that release asexual spores called conidia.
132
Where does sexual reproduction occur in basidiomycetes?
Sexual reproduction occurs within the basidia on the basidiocarp.
133
What forms after mycelia of two different mating types come together?
They form a dikaryotic secondary mycelium.
134
What process does the dikaryotic secondary mycelium undergo?
It goes through mitosis and forms the basidiocarp and basidia.
135
What is a basidium?
A basidium is dikaryotic and its nuclei fuse to form a diploid zygote.
136
What happens to the diploid zygote?
The zygote undergoes meiosis and divides to produce basidiospores.
