Question 1

Which of the following best describes the primary ecological role of phytoplankton (algae) in aquatic environments?

Accepted Answer

They are the base of most aquatic food webs and responsible for most of the photosynthesis and oxygen production in the planet.

Question 2

A patient presents with recurring diarrhea after drinking untreated water. Which protist group is most likely responsible for this infection?

Accepted Answer

Diplomonads

Question 3

Which of the following statements about eukaryotic cells is correct?

Accepted Answer

They have a nucleus with a double membrane and two or more chromosomes composed of DNA and proteins.

Question 4

Which group of protists is characterized by having mitochondria with DNA arranged into interlinked disk-shaped kinetoplasts?

Accepted Answer

Kinetoplastids

Question 5

A red tide event along the Gulf coast results in massive fish kills. Which group of protists is primarily responsible for this phenomenon?

Accepted Answer

Dinoflagellates

Question 6

Which of the following best explains why green algae are considered probable ancestors of land plants?

Accepted Answer

They possess typical chloroplasts and cell walls made only of cellulose.

Question 7

Which of the following protist groups is most likely to be involved in the formation of limestone deposits due to their calcium carbonate shells?

Accepted Answer

Foraminiferans

Question 8

A scientist observes a protist with two types of nuclei: a macronucleus and a micronucleus. Which group does this organism most likely belong to?

Accepted Answer

Ciliates

Question 9

Which of the following is a distinguishing feature of euglenids?

Accepted Answer

They possess a photosensitive eyespot and can switch between autotrophic and heterotrophic nutrition.

Question 10

Which of the following best describes the life cycle of cellular slime molds?

Accepted Answer

They have a two-part life cycle: individual cells aggregate to form a multicellular structure under stress, which then forms a fruiting body that produces spores.

Question 11

Which of the following protist groups is responsible for causing malaria in humans?

Accepted Answer

Apicomplexans (Sporozoans)

Question 12

A marine biologist is studying a photosynthetic protist with a glass-like shell and perforations for substance exchange. Which group does this organism most likely belong to?

Accepted Answer

Diatoms

Question 13

Which of the following is a characteristic of amoebas (Amoebozoans)?

Accepted Answer

They move and engulf food using pseudopodia.

Question 14

Which of the following best explains why brown algae can form large, complex structures such as kelp forests?

Accepted Answer

They have gas bladders for buoyancy and accessory pigments for photosynthesis.

Question 15

A protist is observed to have a feeding groove, move via flagella, and lack mitochondria. To which group does it most likely belong?

Accepted Answer

Excavates

Question 16

Which of the following equations best represents the process of photosynthesis carried out by plant-like protists?

Accepted Answer

$$6CO_2 + 6H_2O \rightarrow C_6H_{12}O_6$ + 6O_2$$

Question 17

Which of the following is true about the nutritional diversity of protists?

Accepted Answer

Protists can be autotrophic, heterotrophic, or mixotrophic, depending on the group.

Question 18

A protist with a silica-based shell and thin pseudopodia is most likely a member of which group?

Accepted Answer

Radiolarians

Question 19

Which of the following best describes the function of the macronucleus in ciliates?

Accepted Answer

It handles all the day-to-day business of the cell.

Question 20

Which of the following protist groups is used in the production of ice cream, cosmetics, and sushi due to their cell wall polysaccharides?

Accepted Answer

Red algae

Diversity and Classification of Protists

Study Guide - Practice Questions

Study Guide - Flashcards