Chapter 28

Question 1

Protist

Answer 1

the informal name of the group of mostly unicellular eukaryotes

Question 2

Protists constitute a _________ group, and Protista is no longer a valid _______

Answer 2

polyphyletic; kingdom

Question 3

T/F: Amitochondriaes are considered the oldest lineage of eukaryotes

Answer 3

False; they were at one time, but they no longer are

Question 4

Amitochondriates

Answer 4

organisms lacking mitochondria

Question 5

The four supergroups of eukaryotes

Answer 5

1) Excavata
2) “SAR” clade
3) Archaeplastida
4) Unikonta

Question 6

Excavata

Answer 6

characterized by its cytoskeleton

Question 7

Some members of the Excavate supergroup have an __________ groove

Answer 7

“excavated” feeding

Question 8

Excavata includes…

Answer 8

diplomonads, parabasalids, and euglenozoans

Question 9

Diplomonads and Parabasalids lack _______, have modified _______, and most live in _______ environments

Answer 9

plastids; mitochondria; anaerobic

Question 10

Diplomonads

Answer 10

have reduced mitochondria (mitoses); derive energy from anaerobic biochemical pathways; have two equal-sized nuclei and many flagella; often parasites

Question 11

Parabasalids

Answer 11

Have reduced mitochondria called hyrogenosomes that generate energy anaerobically

Question 12

the “SAR” clade

Answer 12

a diverse monophyletic supergroup named after its three major clades: Stramenopiles, Alveolates, and Rhizarians

Question 13

The three major clades of the “SAR” clade

Answer 13

1) Stramenopiles
2) Alveolates
3) Rhizarians

Question 14

Stramenopiles

Answer 14

includes many important photosynthetic organisms; most have a hairy and a smooth flagellum; includes diatoms, golden algae, and brown algae

Question 15

Diatoms

Answer 15

unicellular algae with a unique two-part, glass-like wall of silicon dioxide

Question 16

Diatoms are a major component of __________

Answer 16

phytoplankton

Question 17

Golden algae

Answer 17

named for their color resulting from their yellow and brown carotenoids; all are photosynthetic and some are mixotrophs

Question 18

Brown algae

Answer 18

the largest and most complex algae; all are multicellular; most are marine; commonly called seaweed

Question 19

Alternation of generations

Answer 19

the alternation of multicellular haploid and diploid forms

Question 20

Heteromorphic generations

Answer 20

generations in a life cycle that are structurally different

Question 21

Isomorphic generations

Answer 21

generations in a life cycle that look similar

Question 22

Gametophyte

Answer 22

A haploid, multicellular organism that develops from a haploid spore

Question 23

Spore

Answer 23

a minute, typically one-celled, reproductive unit capable of giving rise to a new individual without sexual fusion

Question 24

Alveolata

Answer 24

have membrane enclosed sacs (alveoli) under the plasma membrane

Question 25

alveolate include...

Answer 25

Dinoflagellates, apicomplexans, and ciliates

Question 26

Dinoflagellates

Answer 26

have two flagella and each cell is reinforced by cellulose plates

Question 27

T/F: Toxic "red tides" are caused by dinoflagellate blooms

Answer 27

True

Question 28

Apicomplexans

Answer 28

parasites of animals

Question 29

T/F: Apicomplexans can cause serious human diseases

Answer 29

True

Question 30

Sporozoites

Answer 30

The means by which apicomplexans spread through their hosts

Question 31

T/F: one end of an apicomplexan, the head, contains a complex of organelles specialized for penetrating host cells and tissues

Answer 31

False; the end is actually called the apex

Question 32

most __________ have a sexual and asexual stages that require __________ host species for completion

Answer 32

apicomplexans; multiple

Question 33

The apicomplexan __________ is the parasite that causes malaria

Answer 33

Plasmodium

Question 34

T/F: Plasmodium only requires humans to complete its life cycle

Answer 34

False; it requires both mosquitoes and humans

Question 35

Ciliates

Answer 35

A large varied group of protists; named for the cilia which they use to move and feed

Question 36

Conjugation

Answer 36

When two individuals exchange haploid micronuclei; done in ciliates

Question 37

Conjugations is a _______ and is separate from reproduction

Answer 37

Sexual

Question 38

Archaeplastida

Answer 38

The supergroup that includes red algae, green algae, and land plants

Question 39

Red algae

Answer 39

Red in color due to an accessory pigment called phycoerythrin that masks the green chlorophyll

Question 40

Red algae are usually _________; the largest are seaweeds

Answer 40

multicellular

Question 41

T/F: Green algae are the most abundant large algae in coastal waters of the tropics

Answer 41

False; red algae

Question 42

Green Algae

Answer 42

named for their grass-green chloroplasts

Question 43

______ are descended from the green algae

Answer 43

Plants

Question 44

The two main groups of green algae are _________ and _________

Answer 44

Charophytes and chlorophytes

Question 45

T/F: Chlorophytes are most closely related to land plants

Answer 45

False; Charophytes

Question 46

The supergroup ________ includes animals, fungi, and some protists

Answer 46

Unikonta

Question 47

Unikonta includes two clades: the __________ and the ___________

Answer 47

amoebozoans; opisthokonts

Question 48

T/F: The root of the eukaryotic tree remains controversial

Answer 48

True

Question 49

Many protists are important ________ that obtain energy from the sun

Answer 49

producers