Question 1

Which structural feature is unique to Gram-negative bacteria and contributes to their increased resistance to certain antibiotics?

Accepted Answer

An outer membrane containing lipopolysaccharides

Question 2

A scientist discovers a prokaryote living in a hot spring with a cell wall lacking peptidoglycan and membrane lipids with branched hydrocarbons. To which domain does this organism most likely belong?

Accepted Answer

Archaea

Question 3

Which process allows a bacterium to acquire new genetic material from its environment, potentially leading to antibiotic resistance?

Accepted Answer

Transformation

Question 4

A prokaryote that uses light as an energy source and CO$$_2 as a $$carbon source is classified as which of the following?

Accepted Answer

Photoautotroph

Question 5

Which of the following best explains why nitrogen-fixing bacteria are ecologically important?

Accepted Answer

They convert atmospheric nitrogen ($$N_2) $$into ammonia ($$NH_3$$), making nitrogen available to plants.

Question 6

Which of the following statements about endosymbiosis is correct?

Accepted Answer

Plastids in red and green algae originated from primary endosymbiosis.

Question 7

A protist that can photosynthesize in sunlight but switches to ingesting food particles in the dark is best described as a:

Accepted Answer

Mixotroph

Question 8

Which major supergroup of eukaryotes includes the closest relatives of land plants?

Accepted Answer

Archaeplastida

Question 9

A patient is infected with a bacterium that is resistant to penicillin. Laboratory tests reveal the bacterium has a thin peptidoglycan layer and an outer membrane. Which type of bacterium is most likely responsible?

Accepted Answer

Gram-negative bacterium

Question 10

Which of the following is a correct pairing of a protist clade and a representative organism?

Accepted Answer

SAR – Brown algae

Question 11

Which mechanism of genetic diversity in prokaryotes involves the transfer of DNA via a virus?

Accepted Answer

Transduction

Question 12

Which adaptation allows some prokaryotes to adhere to surfaces and form biofilms, contributing to their survival in hostile environments?

Accepted Answer

Fimbriae

Question 13

Which of the following best describes the difference between Bacteria and Archaea?

Accepted Answer

Archaea have cell walls without peptidoglycan; Bacteria have peptidoglycan in their cell walls.

Question 14

Which life cycle pattern is characterized by alternating multicellular haploid and diploid generations, as seen in some protists and plants?

Accepted Answer

Alternation of generations

Question 15

A researcher observes a unicellular organism with modified mitochondria and two equal-sized nuclei. To which protist clade does this organism most likely belong?

Accepted Answer

Excavata

Question 16

Which of the following is an example of a chemoheterotrophic prokaryote?

Accepted Answer

A bacterium decomposing dead organic matter

Question 17

Which of the following best explains why some Archaea are called extremophiles?

Accepted Answer

They thrive in extreme conditions such as high temperature, salinity, or acidity.

Question 18

Which process involves direct transfer of genetic material between two prokaryotic cells via a pilus?

Accepted Answer

Conjugation

Question 19

Which group within the SAR supergroup includes important photosynthetic organisms that contribute significantly to marine primary production?

Accepted Answer

Diatoms

Question 20

A protist undergoes sexual reproduction, producing gametes that fuse to form a zygote. Which process is directly responsible for restoring the diploid chromosome number?

Accepted Answer

Fertilization

Study Notes: Bacteria, Archaea, and Protists (Chapters 27 & 28)

Study Guide - Practice Questions

Study Guide - Flashcards