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Question 1

What is one way in which a cellular slime mold differs from a plasmodial slime mold?

Answer 1

A cellular slime mold is multicellular.

Question 2

Which of the following is one of the main weaknesses of the proposed classification scheme in which all eukaryotes are divided into five supergroups?

Answer 2

It shows all five supergroups diverging simultaneously from a common ancestor.

Question 2

What do a carnivorous dinoflagellate, a parasitic apicomplexan, and a ciliate have in common?

Answer 2

All three have sacs known as alveoli just beneath their plasma membranes.

Question 3

Which example below is a characteristic shared by diplomonads and parabasalids?

Answer 3

Both lack plastids.

Question 4

All of the following are genera of protists that parasitize humans EXCEPT:

Answer 4

Chlamydomonas

Question 5

Which of these groups includes photosynthetic unicellular organisms with flagella and contractile vacuoles?

Answer 5

Euglenids

Question 6

The term mixotroph indicates that a protist __________.

Answer 6

combines photosynthesis and heterotrophic nutrition

Question 7

Protists are best described as which of the following?

Answer 7

Eukaryotes that are not plants, animals, or fungi

Question 8

Organisms are classified as Excavata based on __________.

Answer 8

morphological studies of the cytoskeleton

Question 9

Which protist group is thought to be most closely related to animals?

Answer 9

Choanoflagellates

Question 10

Which of these groups includes unicellular organisms that, due to the structure of their cell walls, can withstand pressures equal to the pressure under each leg of a table supporting an elephant?

Answer 10

Diatoms

Question 11

Which of the following is not a cellular organelle possessed by a protist?

Answer 11

Sporozoite

Question 12

Which protists were once categorized as fungi due to their multinucleate filaments that resemble hyphae?

Answer 12

Oomycetes

Question 13

The holdfast of brown algae functions in __________.

Answer 13

anchoring the algae

Question 14

Which of these groups includes species that produce a substance that is toxic to humans?

Answer 14

Dinoflagellates

Question 15

Molecular data suggest that plastids originated as __________ engulfed by a heterotrophic eukaryote.

Answer 15

cyanobacteria

Question 16

Parasites of the genus Trypanosoma evade immune responses through what defense?

Answer 16

Frequently changing their surface proteins

Question 17

Which of these groups is characterized by cells that have more than one nucleus?

Answer 17

Ciliates

Question 18

Which of the following does not take place during the process of conjugation?

Answer 18

Reproduction

Question 19

Green algae are divided into two main groups, the charophytes and the __________.

Answer 19

chlorophytes

Question 19

Why have protists been “mixed in” with plants, animals, and fungi under the hypothesis that groups eukaryotes into five supergroups?

Answer 19

Many protists are more closely related to plants, animals, or fungi than they are to each other and recent evidence makes it clear that the former kingdom Protista was paraphyletic

Question 20

Apicomplexans are currently assigned to the chromalveolates because __________.

Answer 20

the apicoplast, a modified plastid, appears to be of red algal origin

Question 21

Which of these groups includes parasitic unicellular organisms with a complex of organelles specialized for penetrating host cells and tissues?

Answer 21

Apicomplexans

Question 22

Although controversial, chromalveolates are proposed as a clade whose common ancestor __________.

Answer 22

engulfed a photosynthetic red alga in a secondary endosymbiosis event

Question 23

Which of the following is the best description of protists’ contribution to photosynthesis?

Answer 23

About 30% of the world’s photosynthesis is performed by protists.

Question 24

The term algae refers to __________.

Answer 24

several diverse groups of photosynthetic protists

Question 25

__________ is a protist that causes late blight of potatoes and was responsible for the Irish potato famine of the 19th century.

Answer 25

Phytophthora infestans

Question 26

Which organisms are capable of producing a "red tide"?

Answer 26

Dinoflagellates

Question 27

cytoskeleton of eukaryotic cell allows it to have

Answer 27

asymmetric shape and to change shape over time

Question 28

protists are

Answer 28

eukaryotes

Question 29

protists reproduce

Answer 29

asexually, sexually, or by meiosis and fertilization

Question 30

photoautotrophs

Answer 30

contain chloroplasts

Question 31

heterotrophs

Answer 31

absorb organic molecules or ingest larger food particles

Question 32

mixotrophs

Answer 32

combine photosynthesis and heterotrophic nutrition

Question 33

protist diversity

Answer 33

endosymbiosis

Question 34

endosymbiosis

Answer 34

a unicellular organism engulfs another cell and becomes an organelle in host cell

Question 35

dinoflagellates

Answer 35

2 flagella - both marine and freshwater phytoplankton - toxic "red tides" are caused by dinoflagellate blooms

Question 36

apicomplexans

Answer 36

parasites of animals - plasmodium; malaria

Question 37

brown algae

Answer 37

kelp or seaweed

Question 38

brown algae are the

Answer 38

largest and most complex multicellular algae

Question 39

brown algal seaweeds have plantlike structure

Answer 39

- holdfast; anchors the alga - stipe; supports leaflike blades

Question 40

brown algae lack

Answer 40

tissues and organs found in plants

Question 41

the diploid generation is called a

Answer 41

sporophyte because it produces spores

Question 42

haploid spores develop into multicellular haploid

Answer 42

gametophytes that produce haploid gametes

Question 43

fertilization of gametes results in a

Answer 43

diploid zygote, which develops into a new sporophyte

Question 44

heteromorphic species

Answer 44

have structurally different gametophytes and sporophytes

Question 45

isomorphic species

Answer 45

have gametophytes and sporophytes that look similar to each other