Question 1

Which of the following best describes the defining criteria for an organism to be classified as a protist?

Accepted Answer

A eukaryote that is not classified as a plant, animal, or fungus.

Question 2

A scientist discovers a new eukaryotic organism that is unicellular, lives in a freshwater pond, and moves using cilia. Which of the following characteristics would most likely be true for this organism?

Accepted Answer

It may obtain food by ingesting organic matter or by photosynthesis.

Question 3

Which of the following is NOT a typical form of locomotion used by protists?

Accepted Answer

Contractile vacuole movement

Question 4

Which reproductive process is correctly matched with the protist that uses it?

Accepted Answer

Amoeba: binary fission

Question 5

Schizogony, a process used by some protists such as Plasmodium, is best described as:

Accepted Answer

A type of asexual reproduction involving multiple rounds of nuclear division before the cell splits into many daughter cells.

Question 6

Brown algae exhibit alternation of generations in their life cycle. Which of the following correctly describes this process?

Accepted Answer

The life cycle alternates between a haploid gametophyte and a diploid sporophyte, with spores produced by meiosis.

Question 7

Which scenario best illustrates secondary endosymbiosis?

Accepted Answer

A eukaryotic cell engulfs another eukaryote that already contains a chloroplast.

Question 8

Why are Unikonta considered important in understanding the evolutionary relationship between animals and fungi?

Accepted Answer

Because Unikonta is the supergroup that contains the lineages leading to both animals and fungi, indicating they share a more recent common ancestor with each other than with plants.

Question 9

Which of the following statements about Archaeplastida is correct?

Accepted Answer

Archaeplastida includes green algae, red algae, and land plants, all of which share a common ancestor that acquired chloroplasts via primary endosymbiosis.

Question 10

A harmful algal bloom (red tide) occurs off the coast, and local authorities warn against eating shellfish. Which group of protists is most likely responsible, and why is this a health concern?

Accepted Answer

Dinoflagellates; they can produce toxins that accumulate in shellfish and cause poisoning in humans.

Question 11

Malaria is caused by a protist in the genus Plasmodium. Which stage of the Plasmodium life cycle is responsible for the symptoms experienced by humans?

Accepted Answer

The asexual reproduction stage in red blood cells, when infected cells rupture.

Question 12

Choanoflagellates are significant to evolutionary biology because:

Accepted Answer

They are the closest living relatives of animals and share cellular features with sponge collar cells.

Question 13

A protist is observed to have a single flagellum and a collar of microvilli. Which of the following is most likely true about this organism?

Accepted Answer

It is a choanoflagellate and provides insight into the origin of animals.

Question 14

Which of the following best explains why modern biology often refers to 'eukaryotic supergroups' rather than the kingdom 'Protista'?

Accepted Answer

Protists are a highly diverse group with members more closely related to plants, animals, or fungi than to each other.

Question 15

A protist is found to reproduce by binary fission. Which of the following equations best represents the number of cells after $$n$$ generations, starting from a single cell?

Accepted Answer

$$N = 2^n$$

Question 16

A marine biologist is studying a protist that is multicellular, lacks complex tissues, and is photosynthetic. Which group is this organism most likely to belong to?

Accepted Answer

Brown algae

Question 17

Which of the following statements about primary and secondary endosymbiosis is correct?

Accepted Answer

Primary endosymbiosis involves a eukaryote engulfing a cyanobacterium, while secondary endosymbiosis involves a eukaryote engulfing another eukaryote that already has a chloroplast.

Question 18

Which of the following is a real-world consequence of the alternation of generations in brown algae for marine ecosystems?

Accepted Answer

It allows for both rapid colonization (via spores) and genetic diversity (via gamete fusion), supporting complex kelp forest ecosystems.

Question 19

A patient presents with fever and chills in a cyclical pattern after returning from a malaria-endemic region. Which process occurring in their body is most directly responsible for these symptoms?

Accepted Answer

Synchronous rupture of red blood cells by asexually reproducing Plasmodium parasites.

General Biology: Protists, Algae, and Eukaryotic Evolution Study Guide

Guida di studio - Domande di pratica

Study guide - Flashcard