Question 1

Which of the following is a key feature that distinguishes eukaryotes from bacteria and archaea?

Accepted Answer

Presence of a nuclear envelope

Question 2

Protists are considered a paraphyletic group. What does this mean in terms of their evolutionary relationships?

Accepted Answer

They do not include all descendants of their most recent common ancestor

Question 3

Which of the following diseases is caused by a protist and transmitted by mosquitoes?

Accepted Answer

Malaria

Question 4

A harmful algal bloom in a coastal area is most likely caused by which group of protists?

Accepted Answer

Dinoflagellates

Question 5

Which of the following best describes the role of photosynthetic protists in aquatic food chains?

Accepted Answer

They act as primary producers, converting $$CO_2$$ into organic molecules via photosynthesis

Question 6

How might fertilizing the ocean with iron help mitigate global climate change?

Accepted Answer

It increases protist populations, which enhances carbon fixation and promotes carbon sinking to the ocean floor

Question 7

Which evidence supports the endosymbiosis theory for the origin of mitochondria?

Accepted Answer

Mitochondria have their own circular DNA and replicate by fission

Question 8

What is the most likely evolutionary origin of the nuclear envelope in eukaryotes?

Accepted Answer

Infoldings of the plasma membrane

Question 9

Which of the following feeding strategies is unique to protists that lack a cell wall?

Accepted Answer

Phagocytosis using pseudopodia

Question 10

A protist that moves using long, lobe-like pseudopodia and lacks a cell wall most likely belongs to which lineage?

Accepted Answer

Amoebozoa

Question 11

Which of the following best explains why sexual reproduction is considered adaptive in protists?

Accepted Answer

It produces genetically variable offspring that may survive changing environments or resist pathogens

Question 12

Which of the following is a real-world example of a protist affecting human society?

Accepted Answer

The Irish potato famine caused by Phytophthora infestans

Question 13

Which lineage of eukaryotes is characterized by the presence of a single posterior flagellum in reproductive cells and flat mitochondrial cristae?

Accepted Answer

Opisthokonta

Question 14

A scientist discovers a unicellular organism with an 'excavated' feeding groove and two nuclei. To which group does it most likely belong?

Accepted Answer

Excavata

Question 15

Which of the following best describes alternation of generations in protists?

Accepted Answer

A life cycle with both multicellular haploid (gametophyte) and multicellular diploid (sporophyte) stages

Question 16

Which structure is a synapomorphy for the Stramenopila lineage?

Accepted Answer

Flagella with hollow, hairlike projections

Question 17

Which of the following is a correct statement about the origin of chloroplasts in eukaryotes?

Accepted Answer

Chloroplasts originated via primary endosymbiosis of a cyanobacterium

Question 18

Which of the following is a real-world application of protist diversity in geology or industry?

Accepted Answer

Foraminiferan shells are used to date rocks during petroleum exploration

Question 19

Which of the following best describes the process of absorptive feeding in protists?

Accepted Answer

Nutrients are taken up directly across the plasma membrane from the environment

Question 20

A protist that is unicellular, contains chloroplasts, and has a cell wall made of cellulose most likely belongs to which group?

Accepted Answer

Plantae (algae)

Diversification of Eukaryotes and Protist Biology

Study Guide - Practice Questions