Chp 28 (Bio) Protists

Front 1

TRUE OR FALSE: protists are unicellular groups of eukaryotes.

Back 1

True. Most protists are unicellular, although there are some colonial and multicellular species.

p. 575

Front 2

TRUE O FALSE: All eukaryotes are protists.

Back 2

FALSE. All protists are eukaryotes, but not the other way around.

p. 575

Front 3

What four things fall under the domain Eukarya?

Back 3

plants, animals, fungi and protists.

p. 575

Front 4

TRUE OR FALSE: Protists are justifiably considered the simplest eukaryotes.

Back 4

TRUE. In multicellular organisms, essential biological functions are carried out by organs. Unicellular protists carry out the same essential functions, but they do so using subcellular organelles, not multicellular organs.

p. 576

Front 5

What are the four main organelles that protists use?

Back 5

nucleus, endoplasmic recticulum, golgi apparatus, and lysosomes.

p. 576

Front 6

TRUE OR FALSE: Some protists have chloroplasts!

Back 6

TRUE. Some protists are photoautotrophs.

p. 576

Front 7

What does it mean for a protist to be a heterotroph?

Back 7

They absorb organic molecules or ingest larger food particles.

p. 576

Front 8

What does it mean for a protist to be a mixotroph?

Back 8

The protist combine photosynthesis and heterotrophic nutrition.

p. 576

Front 9

Are protists sexual or asexual organisms?

Back 9

Some protists are exclusively asexual, others can reproduce sexually (or at least employ the sexual processes of meiosis and fertilization.)

p. 576

Front 10

What is endosymbiosis?

Back 10

The process in which certain unicellular organisms engulf other cells.

p. 576

Front 11

What are endosymbionts?

Back 11

engulfed cells that ultimately become organelles in the host cell.

p. 576

Front 12

What is the theory behind diversity in protists?

Back 12

endosymbiosis.

p. 576

Front 13

What is the name of the bacterium that the first eukaryote acquired its mitochondria from?

Back 13

alpha proteobacterium

p. 576

Front 14

Is an alpha proteobacterium a aerobic or anarobic prokaryote?

Back 14

aerobic prokaryote.

p. 576

Front 15

What is the theory behind secondary endosymbiosis?

Back 15

Red algae and green algae ingested in the food vacuole of heterotriphic eukaryotes and became endosymbionts themselves.

p. 576

Front 16

What evidence is there that the secondary endosymbiosis occurred semi-recently?

Back 16

the engulfed green alga still carries out photosynthesis with its plastids and contains a tiny vestigial nucleus of its own called a nucleomorph.

p. 576

Front 17

What is a nucleomorph?

Back 17

a tiny vestigial nucleus that an organelle contains (such as green algae.)

p. 576

Front 18

What two things underwent secondary endosymbiosis?

Back 18

red algae and green algae.

p. 576

Front 19

What is special about chlorarachniophytes?

Back 19

Their plastids are surrounded by four membrane, which supports the hypothesis of secondary endosymbiosis.

p. 576

Front 20

what are the three common names for unicellular eukaryotes?

Back 20

ciliates, protozoa, flagellates

lecture 6

Front 21

TRUE OR FALSE: Protists are considered a kingdom.

Back 21

FALSE. They are not a valid kingdom, they are a paraphyletic group.

lecture 6

Front 22

TRUE OR FALSE: Protists are the simple of any eukaryotic group.

Back 22

FALSE. Protists are among the most complex and diverse cell forms of any eukaryotic group. (Nutritionally and cell forms)

lecture 6

Front 23

What are the 3 possible types of nutrition for a protist?

Back 23

phototroph, heterotroph, and mixotroph.

lecture 6

Front 24

During endosymbiosis, what was the proteobacterium engulfed?

Back 24

mitochondria

lecture 6

Front 25

During endosymbiosis, what was the cyanobacterium that was engulfed?

Back 25

a plastid.

lecture 6

Front 26

What was the primary endosymbiosis?

Back 26

When a heterotrophic eukaryote engulfed a cyanobacterium.

lecture 6

Front 27

Which three types of protists obviously engulfed a red algae?

Back 27

dinoflagellates, apicomplexans, and stramenopiles

lecture 6

Front 28

Which two types of protists obviously engulfed a green algae?

Back 28

Euglenids, and chlorarachniophyte.

lecture 6

Front 29

Which three groups belong to the supergroup Excavata?

Back 29

diplomonads, parabasalids, and eugelenozoans

lecture 6

Front 30

Under the supergroup excavata, what group does the bacteria Giardia intestinalis fall under?

Back 30

diplomonads.

lecture 6

Front 31

What are the four characteristics of the group diplomonads?

Back 31

1) modified mitochondria called mitosomes
2) Can live anaerobically, glycolysis alone
3) Two equal sized nuclei
4) multiple flagella

lecture 6

Front 32

Which supergroup does the group parabasalid belong?

Back 32

excavata

lecture 6

Front 33

Which group does the protists trichomonas vaginalis belong?

Back 33

parabasalid. trichomonas vaginalis is a human pathogen.

lecture 6

Front 34

What are the two key characteristics of parabasalid?

Back 34

1) hydrogenosomes, or reduced mitochondria
2) Able to generage energy anaerobically

lecture 6

Front 35

What group does the Trypanosoma protist belong to?

Back 35

Euglenozoa

lecture 6

Front 36

What group does the protist leishmania belong to?

Back 36

Euglenozoa

lecture 6

Front 37

TRUE OR FALSE: The Euglenozoa is a simple clade.

Back 37

FALSE. Euglenozoa are a diverse clade.

lecture 6

Front 38

What are the 5 distinguishing features to the euglenozoa?

Back 38

1) Predatory heterotrophs
2) Photosynthetic autotrophs
3) Pathogenic parasites
4) Spiral or crystalline rod of unknown function inside their flagella
5) Includes the kinetoplastids and euglenids.

lecture 6

Front 39

What is a kinetoplastid?

Back 39

Protists which belong to the group Euglenozoa in the supergroup Excavata that have a single, large mitochondrion that contains an organized mass of DNA called a kinetoplast.

lecture 6

Front 40

Do Trypanosoma belong to kinetoplastids or euglenids?

Back 40

kinetoplastids

p. 580

Front 41

What are euglenids?

Back 41

Protists that has a pocket at one end of the cell from which one or two flagella emerge.

p. 581

Front 42

What are three characteristics of Excavata?

Back 42

1) Undulating membrane
2) Divergent mitochondria
3) some members of this diverse group have an "excavated" feeding groove on one side of the cell body.

Front 43

Are the three groups that make up excavata paraphelytic or monophyletic?

Back 43

monophyletic.

p. 580

Front 44

Which seven groups belong to Chromalveolata?

Back 44

Dinoflagellates, apicomplexans, ciliates, diatoms, golden algae, brown algae, and oomycetes.

lecture 6

Front 45

What is common among Chromalveolata?

Back 45

their common ancestor engulfed a single-celled, photosynthetic red alga.

p. 582

Front 46

What are the two large protist clades belonging to chromalveolata?

Back 46

alveolates and stramenophiles.

lecture 6

Front 47

What is a key characteristic to alveolates?

Back 47

they have membrane-bounded sacs (alveoli) under the plasma membrane.

p. 582

Front 48

What are the three subgroups of alveolates?

Back 48

1) Dinoflagellates: a group of flagellates
2) Apicomplexans: a group of parasites
3) Ciliates: move using cilia

p. 582

Front 49

What is a Pfiesteria?

Back 49

a red tide bloom belonging to dinoflagellates.

lecture 6

Front 50

What are the 4 key characteristics of dinoflagellates?

Back 50

1) Diverse group of aquatic mixotrophs and heterotrophs
2) Abundant components of both marine and freshwater phytoplankton
3) Characteristic shape reinforced by internal plates of cellulose
4) Pfiesteria red tide blooms

lecture 6

Front 51

What is an example of an apicomplexan?

Back 51

malaria

lecture 6

Front 52

What are 4 key characteristics of apicomplexans?

Back 52

1) Parasites of animals
2) one end, the apex, contains a complex of organelles specialized for penetrating a host
3) nonphotosynthtic plastid, apicoplast
4) have sexual and asexual stages that require 2 or more hosts for completion.

lecture 6

Front 53

what is an apicoplast?

Back 53

a nonphotosynthetic plastid in an apicomplexan.

lecture 6

Front 54

What are sporozoites?

Back 54

Parasites that spread through their host as tiny infectious cells in apicomplexans.

p. 583

Front 55

What is chloroquine?

Back 55

a plant derived compound that kills malaria...

lecture 6

Front 56

What is the agent of malaria

Back 56

Apicomplexan plasmodium

Front 57

What are four characteristics of ciliates?

Back 57

1) Named for their use of cilia to move and feed.
2) They have two types of nuclei: tiny micronuclei and large macronuclei. (a cell has one or more nuclei of each type)
3) Genetic variation from conjugation
4) Reproduce asexually by binary fission.

p. 585

Front 58

What are the two important characteristics of stramenophiles?

Back 58

1) IMPORTANT photosynthetic organisms as well as some heterotrophs
2) Characteristic flagellu, which has numberous fine, hairlike projections.

p. 585

Front 59

can diatoms be multicellular?

Back 59

No, they are only unicellular.

p. 585

Front 60

What make-up the cell wall of diatoms?

Back 60

hydrated silica (silicon dioxide)

p. 585

Front 61

How does a diatom have the strength that it does?

Back 61

Much of the diatoms' strength comes from the delicate lacework of holes and grooves in their walls.

p. 585

Front 62

How do diatoms reproduce?

Back 62

asexually by mitosis, though sometimes they can reproduce sextually, but not common.

p. 585

Front 63

How do diatoms store energy?

Back 63

in the form of glucose polymer called laminarin, also in oil moleculles.

p. 585

Front 64

what is biological carbon pump?

Back 64

when diatoms sink to the floor. It begins during photosynthesis when diatoms incorporate carbon into their bodies from carbon dioxide in the air.

p. 585

Front 65

What are the 5 key characteristics of golden algae?

Back 65

1) Color from yellow and brown carotenoids.
2) Cells are biflagellated w/flagella at each end of a cell.
3) All are photosynthetic and some mixotrophs.
4) Absorb organic compounds or ingest food through phagocytosis.
5) Most are unicellular, but some are colonial.

p. 586

Front 66

What are the characteristics of brown algae?

Back 66

1) brown or olive color from the carotenoids
2) has a thallus, or algal body that is plantlike
3) Has a holdfast, which anchors the alga
4) Has a stipe, which supports the leaflike blades
5) has blades, which provide the alga's photosynthetic surface.
6) Has cellulose and gel-forming polysaccharides that help cushion the thalli from waves and reduce drying when exposed.

p. 586

Front 67

What is the alternation of generations?

Back 67

The alternation of multicellular haploid and diploid forms.

p. 587

Front 68

What are sporophytes?

Back 68

diploid individuals because they produce spores.

Front 69

Are spores produced by the diploid sporophytes diploid or haploid?

Back 69

haploid, and they move by means of flagella.

p. 587

Front 70

What are zoospores?

Back 70

flagellated spores. They develop into male and female gametophytes which produce gametes.

p. 587

Front 71

What is syngamy?

Back 71

Fertilization. The union of two gametes results in a diploid zygote, which matures and gives rise to new sporophytes.

p. 587

Front 72

What does it mean to be heteromorphic?

Back 72

The sporophytes and gametophytes are structurally different.

p. 587

Front 73

What does it mean to be isomorphic generations?

Back 73

The sporophytes and gametophytes look similar to each other, although they differ in chromosome number.

p. 587

Front 74

What are three key characteristics of oomycetes?

Back 74

1) include water molds, white rusts, and downy mildews
2) Have cell walls made of cellulose instead of the fungi polysaccharide, chitin.
3) Acquire nutrients as decomposers or parasites, DO NOT DO PHOTOSYNTHESIS.

p. 588

Front 75

What three groups make up Rhizaria?

Back 75

1) Chlorarachniophytes
2) Forams
3) Radiolarians

Front 76

What are the key characteristics of chlorarachniophytes?

Back 76

1) include amoeba which move and feed by means os pseudopodia.

Front 77

What are the 4 key characteristics of foraminiferans?

Back 77

1) Forams are named for their porous shells, called tests (made of calcium carbonates)
2) Pseudopodia extends through the pores function in swimming, test formation, and feeding.
3) Nourishments also come from photosynthetic algae living in tests.
4) Marine and fresh water.

p. 589

Front 78

What are the key characteristics that make up radiolarians?

Back 78

1) intricately symmetrical internal skeletals made of silica. (delicate, unlike diatoms)
2) Pseudopodia radiates from central body and reinforced by bundles of microtubules.
3) Microtubules surrounded by cytoplasm that engulfs smaller microorganisms.
4) Uses cytoplasmic streaming to carry prey to main part of cell.

p. 589-590

Front 79

What three things belong to the group Archaeplastida?

Back 79

Red Algae, Green Algae and land plants

lecture 6

Front 80

What two subgroups belong to green algae?

Back 80

chlorophytes and carophyceans

lecture 6

Front 81

What is the key characteristic for Archaeplastida?

Back 81

This group descended from the ancient protist that engulfed cyanobacterium.

p. 590

Front 82

What is the 3 key characteristic of red algae?

Back 82

1) Their reddish brown color is from the accessory pigment (Phycoerythrin), which masks the green of chlorophyll. This allows them to absorb blue and green light which can penetrate deeper waters.
2) Alternate of generations is common.
3) Have no flagellated stages in their live cycle. They depend on water currents to bring gametes together for fertilization.

p. 590

Front 83

What are the key characteristics of green algae?

Back 83

1) Have ultra-structure and pigment composition much like chloroplasts of land plants.
2) Divided into two main groups, clorophytes and charophytes.
3) Mostly freshwater, but many marine as well.

p. 591

Front 84

What are the key characteristics of chlorophytes?

Back 84

1) Form colonies of individual cells and in filamentous forms that contribute to the stringy masses known as pond scum. (Volvox)
2) The formation of true multicellular bodies of cell division and differentiation. (Ulva)
3) Repeated division of nuclei with no cytoplasmic division (Caulerpa.)
4) Both sexual and asexual reproductive stages (sexual stage has biflagellated gamete with cup-shaped chloroplasts)

p. 591

Front 85

What is the main characteristic of charophytes?

Back 85

the algae most closely related to land plants.

p. 592

Front 86

Do bacteria use chlorophyll?

Back 86

No they use bacteriochlorophyll and bacterialrodoxin.

lecture 6

Front 87

What group and supergroup does Bonnemaisonia hamifera belong?

Back 87

Group:Red Algae, supergroup: Archaeplastida.

lecture 6

Front 88

What seven subgroups belong to Unikonta?

Back 88

1) Slime molds
2) Gymnamoebas
3) Entamoebas
4) Nucleariids
5) Fungi
6) Choanoflagellates
7) Animals.

Front 89

What are the two groups belonging to the supergoup Unikonta?

Back 89

Amoebozoans and Opisthokonts.

Front 90

What three subgroups belong to Amoebozoans?

Back 90

1) Slime molds
2) Gymnamoebas
3) Enatomoebas

Front 91

What four groups belong to the group Opisthokonts?

Back 91

1) Nuclearrids
2) Fungi
3) Choanoflagellates
4) Animals

Front 92

What supports the close relationship between amoebozoans and opisthokonts?

Back 92

the myosin proteins in their genes.

p. 593

Front 93

What are the key characteristics of amoebozoans?

Back 93

This clade includes many species of amoebas that have lobe- or tube-shaped, rather than threadlike pseudopodia.

p. 594

Front 94

What are the two different types of slime molds?

Back 94

Plasmodial slime molds and cellular slime molds.

p. 594

Front 95

What is a key characteristics of slime molds?

Back 95

They produce fruiting bodies that aid in spore dispersal.

p. 594

Front 96

Slime molds and fungi resemble each other. What is this an example of?

Back 96

evolutionary convergence.

p. 594

Front 97

What are the key characteristics of plasmodial slime molds?

Back 97

1) They are brightly colored, yellow or orange.
2) They have a mass called a plasmodium which is a single cell of cytoplasm which is undivided and contains many diploid nuclei.
3) Cytoplasmic streaming helps distribute nutrients and oxygen.

Front 98

What is a plasmodium in plasmodial slime molds the result of?

Back 98

It is a product of mitotic nuclear divisions that are not followed by cytokinesis.

p. 595

Front 99

What is the difference between plasmodial slime molds and cellular slime molds?

Back 99

1) Their cells remain separated by individual plasma membranes.
2) They hare haploid organisms (only their zygote is diploid)
3) Their fruiting bodies function in asexual rather than sexual reproduction.

p.596

Front 100

What is a dictyostelium discoideum?

Back 100

a "cheater" slime mold.

p. 596

Front 101

Where are Gymnamoebas found?

Back 101

unicellular protists found in soil and freshwater and marine environments.

p. 596

Front 102

What is a key characteristic of entamoebas?

Back 102

They are parasites that infect all classes of vertebrates.

p. 596

Front 103

What is a key characteristic of opisthokonts?

Back 103

They include animals, fungi and several groups of protists.

p. 596

Front 104

What is DHFR-TS?

Back 104

two essential genes in cells that fused together. Protists have separate cells, but bikonts and unikonts fused the cells together.

lecture 6

Front 105

CONCEPT CHECK 28.1
1) Cite at least four examples of structural and functional diversity among protists.

Back 105

Protists include unicellular, colonial, and multicellular organisms; photoautotrophs, heterotrophs, and mixotrophs; species that reproduce asexually, sexually, or both ways; and organisms with diverse physical forms and adaptations.

Front 106

CONCEPT CHECK 28.1
2) Summarize the role of endosymbiosis in eukaryotic evolution.

Back 106

Strong evidence shows that eukaryotes acquired mitochondria after an early eukaryote first engulfed and then formed an endosymbiotic association with an alpha proteobacterium. Similarly, chloroplasts in red and green algae appear to have descended from a erotrophic eukaryote. Secondary endosymbiosis also played an important role: Various protist lineages acquired plastids by engulfind unicellular red or green algae.

Front 107

CONCEPT CHECK 28.2
1) Why do some biologists describe the mitochondria of diplomonads and parabasalids as "highly reduced"?

Back 107

Their mitochondria do not have an electron transport chain and so cannot function in aerobic respiration.

Front 108

CONCEPT CHECK 28.3
1) Summarize the evidence for and against the hypothesis that the species currently classified as chromalveolates are members of a single clade.

Back 108

Some DNA data indicate that Chromalveolata is a monophyletic group, but other DNA data fail to support this result. In support of monophyly, for many species in the group, the structure of their plastids and the sequence of their plastid DNA suggest that the group originated by a secondary endosymbiosis event (in which a red alga was engulfed). However, other species in the group lack plastids entirely, making the secondary endosymbiosis hypothesis difficult to test.

Front 109

CONCEPT CHECK 28.3
2) Looking back to Chapter 13, which of the three life cycles in Figure 13.6 exhibits alternation of generations? How does it differ from the other two?

Back 109

Figure 13.6b. Algae and plants with alternation of generations have multicellulat haploid stage and a multicellular diploid stage.

Front 110

CONCEPT CHECK 28.5
1) Identify two ways in which red algae differ from brown algae?

Back 110

Many red algae contain an accessory pigment called phycoerythrin, which gives them a reddish color and allows them to carry out photosynthesis in relatively deep coastal watter. Also unlike brown algae, red algae have no flagellated stages in their life cycle and must depend on water currents to bring gametes together for fertilization.

Front 111

CONCEPT CHECK 28.5
2) Why is it accurate to say that Ulva has true multicellularity but Caulerpa does not?

Back 111

Ulva's thallus contains many cells and is differentiated into leaflike blades and a rootlike holdfast. Caulerpa's thallus is composed of multinucleate filaments without cross-walls, so it is essentially one large cell.

Front 112

CONCEPT CHECK 28.6
1) Contrast the pseudopodia of amoebozoans and forams.

Back 112

Amoebozoans have lobe-shaped pseudopodia, whereas forams have threadlike pseudopodia.

Front 113

CONCEPT CHECK 28.6
2) In what sense is "fungus animal" a fitting description of a slime mold? In what sense is it not a fitting description?

Back 113

Slime molds are fungus-like in that they produce fruiting bodies that aid in the dispersal of spores, and they are animal-like in that they are motile and ingest food. However, slime molds are more closely related to guymnamoebas and entamoebas than to fungi or animals.

Front 114

CONCEPT CHECK 28.7
1) Justify the claim that photosynthetic protists are among the most important organisms in the biosphere.

Back 114

Because photosynthetic protists lie at the base of aquatic food webs, many aquatic organisms depend on them for food, either directly or indirectly. (In addition, a substantial percentage of the oxygen produced in photosynthesis on Earth is made by photosynthetic protists.)

Front 115

CONCEPT CHECK 28.7
2) Discuss the range of symbiotic associations that include protists.

Back 115

Protists form mutualistic and parasitic associations with other organisms. Examples include parabasalids that form a mutualistic symbiosis with termites, as well as the oomycete Phytophtora ramorum, a parasite of oak tree.

Front 116

SELF QUIZ
1) Plastids that are surrounded by more than two membranes are evidence of
a) Evolution from mitochondria
b) Fusion of plastids
c) Origin of the plastids from archaea
d) secondary endosymbiosis
e. budding of the plastids from the nuclear envelope.

Back 116

d

Front 117

SELF QUIZ
2) Biologists suspect that endosymbiosis gave rise to mitochondria before plastids partly because
a) the products of photosynthesis could not be metabolized without mitochondrial enzymes.
b) all eukaryotes have mitochondria (or their remnants), whereas many eukaryotes do not have plastids.
c) Mitochondrial DNA is less similar to prokaryotic DNA than is plastid DNA.
d) without mitochondrial CO2 production, photosynthesis could not occur.
e) mitochondrial proteins are synthesized on cytosolic ribosomes, whereas plastids utilize their own ribosomes.

Back 117

b.

Front 118

SELF QUIZ
3) Which group is incorrectly paired with its description?
a) rhizarians -- morphologically diverse group defined by DNA similarities
b) diatoms -- important producers in aquatic communities
c) red algae-- acquired plastids by secondary endosymbiosis
d) apicomplexans -- parasites with intricate life cycles
e) diplomonads -- protists with modified mitochondria.

Back 118

c

Front 119

SELF QUIZ
4) Based on the phylogenetic tree in Figure 28.3, which of the following statement is correct?
a) The most recent common ancestor of Excavata is older than that of Chromalveolata.
b) The most recent common ancestor of Chromalveolata is older than that of Rhizaria
c) The most recent common ancestor of red algae and land plants is older than that of nucleariids and fungi.
d) The most basal (first to diverge) eukaryotic supergroup cannot be determined
e) Excavata is the most basal eukaryotic supergroup.

Back 119

d

Front 120

SELF QUIZ
5) Which protists are in the same eukaryotic supergroup as land plants?
a) green algae
b. dinoflagellates
c) red algae
d) brown algae
e) both a and c

Back 120

e

Front 121

SELF QUIZ 6
6) In life cycles iwth an alternation of generations, multicellular haploid forms alternate with.
a) unicellular haploid forms
b) unicellular diploid forms.
c) multicellular haploid forms.
d) multicellular diploid forms.
e) multicellular polyploid forms.

Back 121

d