$6 \text{CO}_2 + 6 \text{H}_2\text{O} \rightarrow \text{C}_6\text{H}_{12}\text{O}_6 + 6 \text{O}_2$

Question 1

Which of the following statements best explains why protists are considered a paraphyletic group?

Accepted Answer

They include a common ancestor and some, but not all, of its descendants.

Question 2

Which of the following is a key difference between prokaryotic and eukaryotic cells as shown in the provided images?

Accepted Answer

Eukaryotic cells have a membrane-bound nucleus, while prokaryotic cells do not.

Question 3

Which of the following best describes the process of endosymbiosis that led to the origin of mitochondria?

Accepted Answer

A host cell engulfed an aerobic bacterium, which provided ATP and became the mitochondrion.

Question 4

Which equation correctly represents the process of photosynthesis carried out by protists and other photosynthetic organisms?

Accepted Answer

$6 	ext{CO}_2 + 6 	ext{H}_2	ext{O} ightarrow 	ext{C}_6	ext{H}_{12}	ext{O}_6 + 6 	ext{O}_2$

Question 5

Which of the following is a real-world consequence of protist activity in aquatic ecosystems?

Accepted Answer

Protists form the base of the aquatic food chain as primary producers.

Question 6

Which of the following best explains why multicellularity is considered an evolutionary advantage in eukaryotes?

Accepted Answer

It enables specialization of cells, allowing different functions within the same organism.

Question 7

During the Irish Potato Famine, which protist was responsible for the crop failure, and what was the major impact on the population?

Accepted Answer

Phytophthora infestans; caused mass starvation and emigration.

Question 8

Which of the following is NOT a characteristic of mitochondria that supports the endosymbiotic theory?

Accepted Answer

They are larger than most eukaryotic nuclei.

Question 9

Which of the following best describes the role of protists in the global carbon cycle?

Accepted Answer

They act as carbon sinks by forming sedimentary rocks and petroleum deposits.

Question 10

Which of the following is a correct statement about the reproduction of eukaryotes compared to prokaryotes?

Accepted Answer

Eukaryotes can reproduce asexually via mitosis or sexually via meiosis, while prokaryotes reproduce by binary fission.

Question 11

Which of the following feeding strategies is unique to some protists and allows them to ingest food particles much larger than single molecules?

Accepted Answer

Phagocytosis

Question 12

Which of the following is a plausible reason why dinoflagellate blooms (red tides) are dangerous to both marine life and humans?

Accepted Answer

They release neurotoxins that can accumulate in shellfish and cause poisoning in humans.

Question 13

Which of the following best describes the relationship between the mitochondrial genome and bacterial genomes?

Accepted Answer

The mitochondrial genome is closely related to the genome of alpha-proteobacteria.

Question 14

Which of the following is a correct sequence of events in the endosymbiotic origin of mitochondria?

Accepted Answer

Host cell engulfs bacterium → Bacterium lives inside host cell → Bacterium provides ATP to host cell

Question 15

Which of the following is a major difference between the three-domain and two-domain models of the tree of life?

Accepted Answer

The two-domain model groups Eukaryotes within Archaea, while the three-domain model treats them as separate domains.

Question 16

Which of the following best describes the function of the nuclear envelope in eukaryotic cells?

Accepted Answer

It separates the genetic material from the cytoplasm.

Question 17

Which of the following is a correct description of the role of primary producers in the carbon cycle?

Accepted Answer

They fix atmospheric carbon dioxide into organic molecules via photosynthesis.

Question 18

Which of the following is a plausible explanation for why multicellularity evolved independently in several eukaryotic lineages?

Accepted Answer

Multicellularity enables specialization of cells, increasing organismal complexity and adaptability.

Question 19

Which of the following best describes the difference between mitosis and meiosis in eukaryotic life cycles?

Accepted Answer

Mitosis produces genetically identical cells for growth, while meiosis reduces chromosome number and produces gametes.

Diversification of Eukaryotes: Protists and the Eukaryotic Tree of Life

Study Guide - Practice Questions