Eukaryotes Flashcards
1
Q
What does protist giardia cause
A
a diarrheal illness (giardiasis)
2
Q
how is Giardiasis spread
A
contaminated water supplies
3
Q
What does protist refer to
A
informally to a diverse group of microscopic eukaryotes
4
Q
why isn’t protist a formal taxonomic term
A
the organisms do not have a shared evolutionary origin
5
Q
what are algae
A
photosynthetic organisms that can be unicellular or multicellular
6
Q
what are protozoa
A
non photosynthetic motile organisms that are always unicellular
7
Q
what are plankton
A
microorganisms that drift or float in water, moved by currents
8
Q
what are the type of plankton
A
zooplankton
phytoplankton
9
Q
what is a difference between zooplankton and phytoplankton
A
phytoplankton are photosynthetic, zooplankton are motile and non photosynthetic
10
Q
what are trophozoites
A
11
Q
what do trophozoites feed on
A
small particulate food sources such as bacteria
12
Q
when do trophozoite develop into an encapsulated cyst
A
when environmental conditions are too harsh for the trophozoit
13
Q
what is a cyst
A
a cell with a protective wall
14
Q
what is the process where a trophozoite become a cyst called
A
encystment
15
Q
what is the process where cysts become active again
A
excystment
16
Q
when does encystment occur
A
when conditions are favorable for trophozoites
17
Q
what is a protozoan genus capable of encystment
A
eimeria
18
Q
come back to eimeria life cycle
A
19
Q
how does asexual reproduction in protozoans occur
A
binary fission, budding or schizogony
20
Q
what is schizogony
A
when the nuclear of a cell divides multiple times before the cell divides into small cells
21
Q
where are the products of schizogony called
A
merozoites
22
Q
how are merozoites stored
A
in structures called schizonts
23
Q
what type of gametes do sexual protozoans produce
A
haploid gametes that fuse through syngamy
24
Q
is the conjugation process the same in protozoans as bacteria
A
no
25
what kind of gametes do protozoans produce
haploid
26
what does protist conjugation refer to
true form of eukaryotic sexual reproduction between two cells of different mating types
27
what is protist conjugation found in
ciliates
28
what is plasmalemma
plasma membrane in protozoans
29
what do some protozoan plasma membranes have
pellicle
30
what is a pellicle
bands of protein inside the membrane to add rigidity
31
what is ectoplasm
an outer gel layer of cytoplasm with microfilaments of actin in some protist
32
what is endoplasm
inner layer of cytoplasm, a sol region
33
what is a cytostome
a structure used for taking in food through phagocytosis
34
what is a cytoproct
a structure of exocytosis of waste
35
what are cytosines lined with
hair like cilia to sweep in food particles
36
are protozoans heterotrophic or autotrophic
heterotrophic
37
what does it mean to be holozoic
to inject whole food particles through phagozytosis
38
what does it mean to be saprozoic
to ingest small soluble food molecules
39
what do protist use for motility
flagella, cilia and pseudopodia (false feet)
40
what are pseudopodia
cytoplasmic extensions that attach the cell to a surface then allow cytoplasm to flow into the extension moving them `
41
what are contractile vacuoles
organelles that move water out of the cell for osmotic regulation
42
what are kinetoplastids and hydrogenosomes
modified mitochondria
43
what is a polyphyletic group
drop lacking a shared evolutionary origin
44
how is eukaryotic divided
into 6 super groups
45
What are the eukaryotic super groups
excavata
chromalveolata
rhizaria
archaeplastida
amoebozoa
opisthokonta
46
what is included in the amoebozoa group
protozoans that use amoeboid movement
47
What is E histolytica
an amoebozoa that causes dysentery
48
what is acanthamoeba
an amoebozoa that causes keratitis and blindness
49
what I s naegleria fowleri
brain eating amoeba
50
what are eumycetozoa
slime molds
51
what are the two types of slime molds
cellular slime molds and plasmodial slime molds
52
describe cellular slime molds
individual amoeboid cells that periodically aggregate into a mobile slug that then forms a fruity body that produces haploid sproes
53
describe plasmodial slime molds
large multinucleate amoeboid cells that form reproductive stalks to produce spores that divide into gametes
54
what makes dictyostelium discoideum special
it has both single-celled an multi celled life stages with cells showing some degree of differentiation the multi celled form
55
what are the steps of haploid asexual reproduction
56
what are the steps of reproduction of plasmodial slime molds
57
what is included in supergroup chromalveolata
apicomplexans
ciliates
diatoms
dinoflagellates
58
what are apicomplexans
intra or extracellular parasites that have an apical complex and one end of the cell
59
what is the apical complex
a concentration of organelles, vacuoles and microtubules that allow the parasite to enter host cells
60
describe cryptosporidium parvum
apicomplexan that causes intestinal symptoms and epidemic diarrhea when the cysts contaminate drinking water
61
describe theileria
apicomplexan that is transmitted by ticks causing recurring fever that can be deadly
62
describe toxoplasma gondii
apicomplexan that causes toxoplasmosis and can be transmitted from cat feces unwashed fruit and vegetables and undercooked meat
63
who should avoid toxoplasma gondii
pregnant people
64
what amount of poplin us have antibodies for toxoplasmosis
11%
65
what are ciliates
organisms within the chromalveolata that are characterized by the presence of cilia
66
what are cilia used for
locomotion and feeding
67
what makes balantidium coli special
it is the only parasitic ciliate that affects humans by causing intestinal illness but only serious in immune compromised
68
describe paramecium
a ciliate, motile organism with a clearlyvly visible cytostome and cytoproct
69
describe stentor
a ciliate that is sessile and uses cilia for feeding that has a micronucleus and macronucleus
70
describe the micronucleus of stentor
diploid, somatic and used for sexual reproduction by conjucation
71
describe micronucleus of stentor
derived from the micronucleus and becomes polyploid and has a reduced set of metabolic genes
72
what does polyploid mean
multiple sets of duplicate chromosomes
73
how do ciliates reproduce
conjucation
74
what happens to cells in ciliates during conjugation
each cell the diploid micronuclei undergo meiosis, producing eight haploid nuclei each. then all but one haploid micronuclei and the micronucleus disintegrate the remaining micronucleus undergo mitosis. the two cells exchange one micronucleus each which fuses with the remaining micronucleus to form a new genetically different diploid micronucleus come back to this shit it doesn't make sense
75
Describe oomycetes
similar to fungi, called water molds
76
how are oomycetes different from fungi
they have cell walls made of cellulose and diploid
77
how is phytophthora classified
as a oomycetes
78
what does phytophthora cause
irish potato famine
79
what does excavate include
primitive eukaryotes and many parasites wit limited metabolic abilities
80
what do excavate have on the cell surface
a depression
81
what subgroups are included in excavata
fornicata
parabasalia
euglenozoa
82
characteristics of fornicata
What do they have
What do they lack
lacks mitochondria but has flagella
83
what is included in fornicata
giardia lamblia
84
what is giardiasis lamblia
a pathogen that causes diarrheal illness and is spread through cysts from feces that contaminate water
85
what are parabasalia
animal endosymbionts in the guts of termites and cockroaches
86
Describe parabasalia
they have basal bodies with modified mitochondria and large complex cell structure with undulating membrane and often have flagella
87
what is trichomonads a subgroup of
parabasalia
88
what is a pathogen that belongs to trichomonads
trichomonas vaginalis
89
describe the euglenozoa
common in the environment and include photosynthetic and non photosynthetic species, not typically pathogenic, have to flagella, a pellicle, a stigma and chloroplasts
90
what are trypanosomes
parasitic pathogens in the euglenozoa subgroup
91
what pathogens are trypanosomes
T. Bruce
t. cruzi
92
describe t bruce
causes African trypanosomiasis ( African sleeping sickness)
93
what happens in African sleeping sickness
t Brucei colonizes the blood and brain after bing transmitted by a fly
94
symptoms of African sleeping sickness
confusion, difficulty sleeping lack of coordination
95
African sleeping sickness fly stages
96
what disease is transmitted by triatoma spp
chagas via kissing bugs
97
how does chugs affect body
affects heart tissue or digestive system tissue leading to heart failure or digestive or neurological disorders
98
What are the two major groups of parasitic helminths
round worms (Nematoda)
flat worms (platyhelminthes)
99
describe Nematoda
unsegmented worms that have a full digestive system even when parasites,
100
how can some Nematoda be identified
in the feces and near the anus of infected individuals
101
what does monoecious mean
has both male and female reproductive organs
102
what does dioecious mean
having either male or female reproductive organs
103
what is ascaris lumbricoides
the largest nematode intestinal parasite found in humans
104
how long do ascaris lumbricoides get
1 meter
105
what does a. lumbricoides cause
cough and mild abdominal pain to severe intestinal blockage and impaired growth
106
What does enterobius vermicularis cause
pinworm a nematode
107
what does pinworm cause
sleeplessness and itching around the anus where eggs are laid at night
108
where are toxocara Canis found
in dogs and can be transmitted to humans as toxocariasis
109
where is t. cats found
in cats and can be transmitted to humans as toxocariasis
110
what does toxocariasis cause
larval migrant resulting in vision loss, eye inflammation, fever, fatigue, coughing, and abdominal pain depending on if in infects the eye or viscera
111
what does nectar Americans / ancylostoma duodenal cause
hookworm a nematode
112
what does hookworm cause
abdominal pain, diarrhea, loss of appetite, weight loss, fatigue, anemia
113
how is trichinosis contracted
consuming undercooked meat that releases the larvae and allows them to encyst I muscles
114
signs of trichinosis
fever, muscle pain, digestive problems, can lead to lack of coordination, breathing and heart problems and death
115
what does dirofilaria immitis cause
heart worm in dogs
116
how's dirofilaria immitis transmitted
mosquitos
117
what is included in platyhelminthes
flukes and tapeworms
118
what are flukes (trematodes)
nofsegmented flatworms that have an oral sucker and attach to the inner walls of intestines, lungs, large blood vessels and liver
119
what are clonorchis and opisthorchis
liver flukes
120
what is fasciolopsis buski
intestinal fluke
121
what is paragonimus westermani
oriental lung fluke
122
where are schistosome mansoni, s. haematobium and s. japonicum found
freshwater snails
123
what do schistosome mansoni, s. haematobium and s. japonicum cause
schistosomiasis lungs, then to the liver, and other organs
124
what are tape worms
platyhelminths that are segmented flatworms that have suckers or hooks ash the scolex region
125
what is the scolex region
head region
126
what do tapeworms use their hooks and suckers for
to attach to the wall of the small intestine
127
what is the body of tapeworms made of
segments called proglottids that contain reproductive structures
128
what happens to the reproductive structures in tapeworms
they detach when gametes are fertilized releasing gravid proglottids with eggs,
129
what happens to tape worm eggs after they are released
an intermediate Ost consumes the eggs and they hatch into larval form called oncosphere
oncosphere migrates to a tissue or organ in intermediate forms and becomes cysticerci
once eaten by definitive host the cysticerci become adult tape worms in the digestive system
130
what is Taenia saginata
beef tapeworm
131
what is t. solium
pork tapeworm
132
how do tapeworms enter humans
undercooked meat
133
where are adult tapeworms found
intestine
134
where are larval tapeworms found
other places such as smooth muscle
135
when is the pork tapeworm more dangerous
when the larvae leave the intestine and enter other tissue such as CNS
136
what is diphylobothrium latum
the larger tapeworm that is in undercooked fish. it can grow to 15 meters
137
what is echinococcus granulosus
dog tapeworm that can infect humans and uses dogs as important hosts
138
life cycle of tape worm
1. eggs in feces are passed to environment
2. cattle and pics become infected by ingesting
3. onconospheres hatch penetrate intestinal wall and circulate to musculature
4. humans are infected by ingesting
5. scolex attaches to intestine
6. become adults in small intestine
139
life cycle of schistosoma spp.
140
what is mycoses
illnesses caused by fungi
141
what does it mean that fungi are opportunistic
they cause infections when the hosts immune system is down an not normally health people
142
what makes fungi important
they act as decomposers and are critical for food such as cheese,
major source of antibiotics such as penicillin
143
what are hyphae
filaments that make up molds
144
what is a mycelium
tangled network formed of hyphae that form the thallus
145
what is a thallus
body of fleshy fungi
146
what are septet hyphae
hyphae that have walls between the cells
147
what are coenocytic hyphae
hyphae that lack walls and cell membranes between the cells
148
what are pseudohypha
chains of yeast daughter cells
149
what does it mean to by a dimorphic fungi
they have more than one appearance in their life and can appear to be yeast or molds
150
what causes dimorphic fungi to change their appearance
response to environment such as nutrient availability, temperature
151
name 2 dimorphic yeasts
histoplasmosis capsulatum
Candida albicans
152
what does h. hapsulatum cause
lung disease histoplasmosis
153
what does c. albicans cause
vaginal yeast infections, oral thrush and candidiasis of the skin
154
what are the differences in fungal cell walls and membranes
cell walls contain chitin instead of cellulose
instead of cholesterol in their cell membrane they have different stools called ergosterols
155
what is the target of anti fungal drugs
ergosterols
156
how do fungus reproduce
sexually through cross or self fertilization or asexually
157
what do haploid fungi form
hyphae that have gametes at the tip
158
what is plasmogamy
when the cytoplasms of the + and - gametes fuse producing 2 dusting nuclei
159
what is a dikaryptic cell
fungi with 2 nuclei
160
what is karyogamy
when fungi nuclei fuse to create a diploid zygote
161
what do fungi form as a result of meiosis
spores that germinate to start the haploid stage
162
what are the different names for sexually produced fungal spores
zygospores
ascopspores
basidiospores
163
what is the life cycle of the zygomycete
1. germination (mycelia form + and - have gametangia form between them
2. plasmogamy -fusion between + and- resulting in zygosporangium with multiple haploid nuclei
3. karyogamy- nuclei fuse to form a zygote with multiple diploid nuclei
4. meiosis and germination- a sporangium grows on a short stalk and haploid spores form inside
164
what do ustilagomycetes and urediniomycetes include
plants as rusts and smuts
165
what are rusts and smuts
masses on plants rusts (red) smuts (dark)
166
what does glomeromycota include
mycorrhizal fungi
167
what makes mycorrhizal fungi important
they have a symbiotic relationship with plant roots and promote growth my acting like an extended root system
168
describe glomeromycota
obligate symbionts
169
how do plants help glomeromycota
glomeromycota receives carbs from the plant and the plant
170
describe chytridiomycetes
small fungi that are aquatic and have flagellated, motile gametes,
171
what are chytridiomycetes (chytrids) associated with
amphibian declines
172
describe zygomycota
saprophytes with coenocytic hyphae and haploid nuclei
173
how do zygomycota reproduce
asexually with zygospores that have hard walls formed from the fusion reproductive cells
174
what makes zygomycetes important
some are crop pathogens
175
what is rhizopus stolonifer
a zygomycetes that is an important bread mold that also causes rice seedling blight
176
what is mucor
a genus of fungi that can cause necrotizing infections but most species are intolerant of temperatures in the human body.
177
what do ascomycota include
fungi that are used as food and some that cause food spoilage and human pathogens
178
what do ascomycota have
septet hyphae and cup shaped fruiting bodies called ascocarps
sexually produced ascospores and asexual spores conidia
179
what makes aspergillus important
they are ascomycota fungi that cause allergy and infection and useful in research in the production of fermented alcoholic beverages
180
what is aspergillus flavus
an ascomycota fungi that is a contaminant of nuts and stored grains and produces aflatoxin
181
what is aflatoxin
a toxin and carcinogen
182
what is neurospora crass useful for
genetic research because the spores produced by meiosis are kept inside the ascus I a row that reflects cell division the produced them giving a direct view of segregation and assortment of genes
183
what are trichophyton, microsporum and epidrmopyton
ascomycetes fungi that are dermatophytes that are pathogenic and cause sin infections such as athletes foot jock itch and ringworm
184
What is blastomyces dermatitidis
a ascomycetes fungi that is dimorphic and can cause blastomycosis
185
what is blastomycosis
a respiratory infection that that can become disseminated to other body sites and lead to death
186
what is histoplasmosis capsulatum
a ascomycetes dimorphic fungus associated with birds and bats in Ohio and Mississippi River valleys
187
what does coccidioides immitis cause
Valley fever
188
what are saccharomyces yeasts
unicellular ascomycetes with haploid and diploid stages
189
what is s. cerevisiae
a saccharomyces yeast that includes bakers yeast
190
What is the ascomycete life cycle
1. plasmogamy and mitosis- ascogonium and antheridium fuse, mitosis and cell division result in many dikaryptic hyphae that form a fruiting body called ascocarb
2. karyogamy- nuclei in the sci fust to form a diploid zygote
3. meiosis- an ascus with four haploid nuclei is formed
4.mitosis and cell division- 8 haploid ascospores are formed
5. dispersal and germination
191
what are basidiomycota
fungi that have basidia that produce basidiosprores with fruiting bodies called basidiocarps
192
what are basidiospores
spores produced through budding
193
what do basidiomycota include
rusts
stinkhorns
puffballs
mushrooms
194
what is cryptococcus neoformans
a basidiomycota fungus found as yeast in the environment that can cause lung infections,
195
what is agricus campestris
a basidiomycete that is an edible meadow mushroom
196
what is amanita phalloides
a poisonous mushroom known as the death cap and whose deadly toxins are used to study transcription
197
basidiomycete life cycle
1. germination- mycelia form (+ and -)
2 plasmogamy- fusion between = and - mating results in formation of a dikaryptic mycelium
3. mitosis- a basidiocarp forms
4. karyogamy- basidia form diploid nuclei
5. meiosis - four haploid nuclei are formed in the basidium
6. cell division- four basidiospore are formed
7. dispersal and germination
198
what are micosporidia
unicellular fungi that are obligate intracellular parasites
199
what do microsporidia lack
mitochondria
peroxisomes
centrioles
200
what do microsporidia spores release
polar tubule the pierces the host cell zebrine to allow the fungi to Gain entry into the cell
201
what are microsporidia infections called
microsporidiosis
202
what is enterocystozoan bieneusi
a pathogenic microsporidia that causes diarrhea, cholecystitis and respiratory illness
203
what are algae
autotrophic protist that can be unicellular or multicellular
204
what supergroups can algae be found in
chromalveolata
archaeplastida
205
what algae are in chromalveolata
dinoflagellates
diatoms
golden algae
brown algae
206
what algae are found in archaeplastida
red algae
green algae
207
what makes algae important
they are responsible for 70 percent of oxygen and organic matter I aquatic environment s
208
what is algae a source for
agar, agarose and carrageenan solidifying agents used in food production
209
when do harmful algal blooms occur
when algae grow quickly and produce dense population that produce high concentrations of toxins that impair liver and nervous system functions
210
what are pyrenoids
structures in chloroplasts
211
what do pyrenoids do
synthesize and store starch
212
how do chloroplasts in algae differ
in their number of membranes indicative of secondary or tertiary endosymbiotic events
213
what do the primary chloroplast I algae have
tow membranes, one from the ancestral cyanobacteria and one from the engulfing cell
214
what algae gets confused with plants
seaweed
215
what differences do green algae share with plants
they do not have true tissues or organs
they do not have a waxy cuticle to prevent desiccation
216
why aren't euglenozoa considered algae
they feed and are motile
217
what supergroups are algae classified in
chromalveolata and archaeplastida
218
what brands of algae fall under chromalveolata
dinoflagellates and stramenopiles
219
what are dinoflagellates
marine organisms that are an important component of plankton
220
what are the nutritional types of dinoflagellates
can be heterotrophic, phototrophic or mixotrophic
221
what do dinoflagellates have
two flagella that make them whirl
some have cellulose plates or theca as armor
some produce neurotoxins causing paralysis
222
how does exposure to dinoflagellates happen
contact with water with dinoflagellate toxins or by feeding on organisms that have eaten it
223
what happens when Dinoflagellates become dense
a red tide
224
what is a red tide
a harmful algae bloom
225
what are gonyaulaz and alexandrium
major dinoflagellate toxin produces that cause paralytic shellfish poisoning
226
what is pfiesteria piscicida
a dinoflagellate that is known as fish killer and can cause memory loss and confusion in humans exposed to water containing it
227
what do stramenopiles include
golden algae and brown algae and the diatoms
228
what are the photosynthetic pigments in stramenopiles
chlorophyl and fucoxanthin
229
what is the storage carbohydrate of stramenopiles
chrysolaminarin
230
how do diatoms reproduce
sexually and asexually
231
what do male gametes of centric diatoms have
flagella that provide directed movement to seek female gametes for sexual reproduction
232
what are frustules
outer cell walls of crystalized silica in diatoms
233
what important function do diatoms have
their fossilized remains produce diatomaceous earth that is used for filtration and insulation
234
what are phaeophyta
brown algae that are multicellular marine seaweeds
235
describe brown algae
large with leaf-like blades, stalks and holdfasts
236
what are holdfasts
structures of brown algae that are used to attach to substrate
237
what do brown algae use as storage carbohydrate
laminarin
238
are holdfasts true leaves stems or roots
no
239
what is included in archaeplastids
green algae (chlorophyta)
red algae (rhodophyte)
more gren algae (charophyte) and land plants
240
what is the most similar algae to land plants
charaphyta
241
how are charaphyta similar to land plants
they share a mechanism of cell division
use chlorophyl a and chlorophyl b
cellulose cel walls and starch as a carb storage molecule
242
what is chlamydomonas
a green alga that has a single large chloroplast, two flagella and a stigma (eyespot)
243
what is chlorella
a nonmotile, large, unicellular alga
244
what is acetabularia
large unicellular green alga
245
what is volvox
a colonial, unicellular alga
246
what is ulva
a large multicellular green alga also known as sea lettuce because of large edible green blades
247
describe red alga
they can can be unicellular or multicellular and have rigid cell walls containing agar or carrageenan
248
what od lichens contribute to
soil production by breaking down rocks
early colonizers I soilless environment such as lava flows
they cyanobacteria I some can fix nitrogen
important soil stabilizers
food for caribou
produce compounds with antibacterial effects
249
what is a lichen
a combination of green alga or cyanobacterium and fungus living in a symbiotic relationship
250
what makes lichen special
unlike algae they can grown on any surface especially rocks or as epiphytes
251
what does it mean to be an epiphyte
can grow on other plants
252
what is the relationship between fungi and algae
mutualism or controlled parasitism
253
how do fungus benefit from algae
obtain photosynthates
254
how do algae benefit from fungus
allows them to grow in drier environment
255
why would fungi and algae be considered controlled parasitism
the photosynthetic organism grows less well than it would without the fungus
256
descibe the life cycle of lichens
slow growing and can live for centuries
257
what makes lichens useful
they are used I foods and to extract chemicals as dyes or antimicrobial substances. they are sensitive to pollution making the environmental indicator
258
what do lichens have
a body called a talus, a cortex and a medulla
259
what is a cortex
tightly packed fungal outerlayer
260
what is a medulla
loosely packed fungal inner layer
261
what are rhizines
hyphal bundles in lichens that attach to substrate
262
how are lichens classified
as fungal
263
what groups are lichens in
ascomycota and basidiomycota
264
what are the types major of lichens
crustose lichens
foliose lichens
fruticose lichens
265
describe crustose lichens
lichens tightly attached to the substrate with a crusty appearance
266
describe foliose lichens
lichens with a leaf-like lobe that may only be attached at one point in the growth form and have a second cortex below the medulla
267
describe fruticose lichens
have rounded structures and an overall branched appearance
268
which genus includes the causative agent for malaria
269
which protist is a concern because of its ability to contaminate water supplies and cause diarrheal illness
270
a fluke is classified I which group
271
A nonsegmented worm is found during a routine colonoscopy of an individual who reported having abdominal cramps, nausea, and vomiting. This worm is likely which of the following?
A segmented worm has male and female reproductive organs in each segment. Some use hooks to attach to the intestinal wall. Which type of worm is this?
272
Mushrooms are a type of which of the following?
273
what is the most common cause of human yeast infections
274
Which of the following is an ascomycete fungus associated with bat droppings that can cause a respiratory infection if inhaled?
275
Which of the following is an ascomycete fungus associated with bat droppings that can cause a respiratory infection if inhaled?
agar
276
Which is the term for the hard outer covering of some dinoflagellates?
You encounter a lichen with leafy structures. Which term describes this lichen?
277
Which of the following is the term for the outer layer of a lichen?
278
The fungus in a lichen is which of the following?
279
The plasma membrane of a protist is called the __________.
280
Animals belong to the same supergroup as the kingdom __________.
281
Animals belong to the same supergroup as the kingdom __________.
282
A species of worm in which there are distinct male and female individuals is described as _________.
283
Nonseptate hyphae are also called _________.
284
Unicellular fungi are called _________.
285
Some fungi have proven medically useful because they can be used to produce _________.
286
Structures in chloroplasts used to synthesize and store starch are called ________.
Algae with chloroplasts with three or four membranes are a result of ________ ________.
