Protists Flashcards
1
Q
Are protists prokaryotes or eukaryotes?
A
Eukaryotes
2
Q
Protists are
a) single celled
b) multicellular
A
a) single celled
3
Q
Mitochondria likely evolved from…
A
An endosymbiotic relationship with aerobic prokaryotes
4
Q
Chloroplasts likely evolved from…
A
An endosymbiotic relationship with photosynthetic bacteria
5
Q
What are nucleomorphs?
A
Functional vestigial nuclei of eukaryotes that are endosymbionts in a host cell
6
Q
Define vestigial
A
Reduced/reminant
7
Q
What are the 4 main divisions of protists?
A
- Excavata
- SAR
- Archaeplastida
- Unikonta
8
Q
Sub divisions of Excavata
A
- Diplomonads
- Parabasalids
- Euglenozoans
9
Q
Trichomonas vaginalis is an example of…
A
A parabasalid
10
Q
Trypanosomes are an example of…
A
Euglenozoana
11
Q
Giardia is an example of…
A
Diplomonadida
12
Q
SAR stands for
A
Stramenopiles
Alveolates
Rhizarians
13
Q
What are the key characteristics of stramenopiles and examples?
A
2 flagella: 1 smooth, 1 hairy
- Diatoms
- Brown algae
- Oomycetes
14
Q
What are the key characteristics of alveolates and examples?
A
Air sacs
- dinoflagellates
- apicomplexans
- ciliates
15
Q
What are the key characteristics of rhizarians and examples?
A
Possess pseudopodia for locomotion and feeding
- Radiolorians
- Forams
- Cercozoans
16
Q
What does alveoli mean?
A
Sac
17
Q
Malaria is an example of
A
An apicomplexan with 2 hosts
18
Q
What are the key groups of Archaeplastida? (5)
A
- Red algae
- Green algae
- Plants
- Chlorophytes
- Charophytes
19
Q
What are the key groups of Unikonta? (7)
A
- Tubulinids
- Slime moulds
- Entamoebas
- Nucleariids
- Fungi
- Choanoflagellates
- Animals
20
Q
What are some examples of symbiotic protists? (2)
A
- Wood digesting (termites and cockroaches)
- Cellulose digesting (rumen)
21
Q
Phytophthora ramorum is also known as…
A
Tree killer
- causes sudden oak death
22
Q
Phytoplankton is an example of
A
A photosynthetic protist
23
Q
What are the three domains of life?
A
1.Bacteria
2. Archaea
3. Eukarya
24
Q
What is the endosymbiotic theory?
A
The theory that mitochondria and plastids originated as prokaryotic cells engulfed by an ancestral eukaryotic cell.
25
Protists
A diverse group of eukaryotic microorganisms
26
Which domain do protists belong to?
Eukarya
27
Why was the kingdom Protista abandoned?
Some protists are more closely related to plants
28
What provides structural support in eukaryotic cells?
Cytoskeleton
29
What is a common characteristic of most protists?
They are unicellular.
30
Protist
A eukaryotic organism that is not a plant
31
Cytoskeleton
A network of fibers that provides structural support and enables eukaryotic cells to maintain asymmetric forms and change shape.
32
What is a unique feature of some dinoflagellate protists?
An ocelloid
33
What type of nutrition do mixotrophic protists exhibit?
Both photosynthesis and heterotrophic nutrition
34
Which organelles are commonly found in protists?
Nucleus
35
How do unicellular protists carry out essential biological functions?
Using subcellular organelles
36
What is the primary function of contractile vacuoles in protists?
Pumping excess water from the cell
37
What reproductive methods are found among protists?
Asexual and sexual reproduction
38
What are the three types of nutritional strategies found in protists?
1. Photoautotrophy
2. Heterotrophy
3. Mixotrophy.
39
From which bacterial lineage did mitochondria arise?
Alpha proteobacterium
40
What evidence suggests that mitochondria evolved before plastids?
Structural biochemical and DNA sequence data
41
What is the common ancestor of plastids?
Cyanobacterium
42
What group of archaea is identified as the sister group of the eukaryotes?
Lokiarchaeotes
43
What feature of the host cell enabled it to engulf the alpha proteobacterium?
A cytoskeleton that enabled it to change shape
44
What is secondary endosymbiosis?
When a eukaryotic cell engulfs another eukaryotic cell that has already undergone primary endosymbiosis
45
What is a nucleomorph?
A tiny vestigial nucleus within an engulfed cell
46
Which was once thought to be the first lineage to diverge from all other eukaryotes?
Amitochondriate protists
47
What recent discovery has changed the classification of some amitochondriate protists?
They have been shown to have reduced mitochondria.
48
What is the current hypothesis about the divergence of the four supergroups of eukaryotes?
They diverged simultaneously from a common ancestor.
49
Which of the following is a novel group of protists described in 2018?
Hemimastigophores
50
What is a challenge in understanding the phylogeny of protists?
Ongoing changes in hypotheses due to new data.
51
What characteristic feature is associated with some members of the Excavata clade?
An 'excavated' feeding groove
52
Which of the following groups is included in the Excavata clade?
a) Diatoms
b) Diplomonads
c) Amoebozoans
d) Ciliates
B
53
What is the basis for the original proposal of the Excavata clade?
Morphological studies of the cytoskeleton
54
Which of the following statements about the Excavata clade is true?
a) It includes protists with modified mitochondria and unique flagella.
b) It includes protists with cilia
c) It is universally accepted as monophyletic
d) It includes only photosynthetic protists
A
55
Which of the following groups is NOT part of the Excavata clade?
a) Euglenozoans
b) Amoebozoans
c) Parabasalids
d) Diplomonads
B
56
Protist
An informal term applied to any eukaryote that is not a plant animal or fungus. Most protists are unicellular though some are colonial or multicellular.
57
Dinoflagellate
A member of a group of mostly unicellular photosynthetic algae with two flagella situated in perpendicular grooves in cellulose plates covering the cell.
58
Mixotroph
An organism that is capable of both photosynthesis and heterotrophy.
59
Ciliate
A type of protist that moves by means of cilia.
60
Alveolates
One of the three major subgroups for which the SAR eukaryotic supergroup is named. This clade arose by secondary endosymbiosis and its members have membrane-enclosed sacs (alveoli) located just under the plasma membrane.
61
Amoeba
A protist characterised by the presence of pseudopodia.
62
Euglenid
A protist (such as Euglena or its relatives) characterised by an anterior pocket from which one or two flagella emerge.
63
Diplomonad
A protist that has modified mitochondria
64
Brown algae
A multicellular photosynthetic protist with a characteristic brown or olive colour that results from carotenoids in its plastids. Most brown algae are marine and some have a plantlike body.
65
Red alga
A photosynthetic protist
66
Rhizarians
One of the three major subgroups for which the SAR eukaryotic supergroup is named. Many species in this clade are amoebas characterised by threadlike pseudopodia.
67
Opisthokont
A member of an extremely diverse clade of eukaryotes that includes
1. fungi
2. Animals
3. Several closely related groups of protists.
68
Unikonta
One of four supergroups of eukaryotes proposed in a current hypothesis of the evolutionary history of eukaryotes. This clade consists of amoebozoans and opisthokonts.
69
Stipe
A stem like structure of a seaweed.
70
SAR
One of four supergroups of eukaryotes proposed in a current hypothesis of the evolutionary history of eukaryotes. This supergroup contains a large and extremely diverse collection of protists from three major subgroups: - stramenopiles
- alveolates
- rhizarians.
71
Archaeplastida
One of four supergroups of eukaryotes proposed in a current hypothesis of the evolutionary history of eukaryotes. This monophyletic group (which includes red algae green algae and plants) descended from an ancient protistan ancestor that engulfed a cyanobacterium.
72
Isomorphic
Referring to alternating generations in plants and certain algae in which the sporophytes and gametophytes look alike although they differ in chromosome number.
73
Conjugation
a) In prokaryotes
b) In ciliates
(a) The direct transfer of DNA between two cells that are temporarily joined. When the two cells are members of different species conjugation results in horizontal gene transfer.
(b) A sexual process in which two cells exchange haploid micronuclei but do not reproduce.
74
Excavata
One of four supergroups of eukaryotes proposed in a current hypothesis of the evolutionary history of eukaryotes. Excavates have unique cytoskeletal features and some species have an “excavated” feeding groove on one side of the cell body.
75
Secondary endosymbiosis
A process in eukaryotic evolution in which a heterotrophic eukaryotic cell engulfed a photosynthetic eukaryotic cell which survived in a symbiotic relationship inside the heterotrophic cell.
76
Foram
(foraminiferan) An aquatic protist that secretes a hardened shell containing calcium carbonate and extends pseudopodia through pores in the shell.
77
Heteromorphic
Referring to a condition in the life cycle of plants and certain algae in which the sporophyte and gametophyte generations differ in morphology.
78
Kinetoplastid
A protist (such as a trypanosome) that has a single large mitochondrion that houses an organised mass of DNA.
79
Test
In foram protists - a porous shell that consists of a single piece of organic material hardened with calcium carbonate.
80
Radiolarian
A protist (usually marine) with a shell generally made of silica and pseudopodia that radiate from the central body.
81
Amoebozoan
A protist in a clade that includes many species with lobe- or tube-shaped pseudopodia.
82
Holdfast
A rootlike structure that anchors a seaweed.
83
Euglenozoan
A member of a diverse clade of flagellated protists that includes predatory heterotrophs photosynthetic autotrophs and pathogenic parasites.
84
Stramenopiles
- One of the three major subgroups for which the SAR eukaryotic supergroup is named.
- This clade arose by secondary endosymbiosis and includes diatoms and brown algae.
85
Parabasalid
A protist (such as a trichomonad) with modified mitochondria.
86
Algae
A general term for any species of photosynthetic protist including both unicellular and multicellular forms. Algal species are included in three eukaryote supergroups (Excavata SAR and Archaeplastida).
87
green algae
A photosynthetic protist (named for green chloroplasts that are similar in structure and pigment composition to the chloroplasts of plants). Green algae are a paraphyletic group; some members are more closely related to plants than they are to other green algae.
88
Diatom
Photosynthetic protist in the stramenopile clade; diatoms have a unique glass-like wall made of silicon dioxide embedded in an organic matrix.
89
Cercozoan
An amoeboid or flagellated protist that feeds with threadlike pseudopodia.
90
Apicomplexan
A group of alveolate protists, this clade includes many species that parasitise animals. Some apicomplexans cause human disease.
