Question 1

Which of the following statements best explains why prokaryotes are found in nearly every environment on Earth?

Accepted Answer

Prokaryotes have evolved a wide range of structural and metabolic adaptations that allow them to survive in diverse environments.

Question 2

Based on the phylogenetic tree of life, which domain is the sister group to Archaea?

Accepted Answer

Eukarya

Question 3

Which of the following is a unique characteristic of Archaea compared to Bacteria and Eukarya?

Accepted Answer

Some membrane lipids contain branched hydrocarbons.

Question 4

A scientist discovers a prokaryote living in a hot spring at 90°C. Which group is this organism most likely to belong to?

Accepted Answer

Archaea

Question 5

Which of the following best describes the process and significance of horizontal gene transfer in prokaryotes?

Accepted Answer

It allows genes to be transferred between different species, increasing genetic diversity and complicating phylogenetic relationships.

Question 6

Which of the following groups of bacteria is responsible for causing diseases such as Lyme disease and syphilis?

Accepted Answer

Spirochetes

Question 7

A researcher is studying a prokaryote that can only survive inside animal cells and is responsible for a common sexually transmitted infection in the United States. To which group does this organism most likely belong?

Accepted Answer

Chlamydias

Question 8

Which of the following is true regarding the cell wall composition of Bacteria, Archaea, and Eukarya?

Accepted Answer

Bacteria have peptidoglycan in their cell walls, Archaea do not, and Eukarya lack cell walls made of peptidoglycan.

Question 9

Which of the following best explains why molecular systematics has been important in understanding prokaryotic diversity?

Accepted Answer

It allows scientists to analyze genetic data, revealing evolutionary relationships that are not apparent from morphology alone.

Question 10

Which of the following is a defining feature of cyanobacteria?

Accepted Answer

They are photosynthetic and produce oxygen as a byproduct.

Question 11

A prokaryote is found to have a circular chromosome, no nuclear envelope, and its membrane lipids contain some branched hydrocarbons. Which domain does it most likely belong to?

Accepted Answer

Archaea

Question 12

Which of the following best describes the evolutionary relationship between Bacteria, Archaea, and Eukarya?

Accepted Answer

Archaea and Eukarya share a more recent common ancestor with each other than with Bacteria.

Question 13

Which of the following is NOT a characteristic of Gram-positive bacteria?

Accepted Answer

They have an outer membrane outside the peptidoglycan layer.

Question 14

Which of the following best explains why it is difficult to determine phylogenetic relationships among prokaryotes?

Accepted Answer

Horizontal gene transfer has caused genes to move between distantly related species, obscuring evolutionary lineages.

Question 15

Which of the following statements about extremophiles is correct?

Accepted Answer

They are organisms, often Archaea, that thrive in environments with extreme conditions such as high temperature or salinity.

Question 16

A newly discovered prokaryote has the following characteristics: no nuclear envelope, peptidoglycan in its cell wall, and unbranched membrane lipids. To which domain does it belong?

Accepted Answer

Bacteria

Question 17

Which of the following best describes the role of proteobacteria in the environment?

Accepted Answer

They are a large and diverse group of Gram-negative bacteria that include both beneficial and pathogenic species.

Question 18

Which of the following is a correct comparison of the three domains of life regarding the presence of a nuclear envelope?

Accepted Answer

Eukarya have a nuclear envelope, while Bacteria and Archaea do not.

Prokaryotic Diversity and Evolution: Structure, Lineages, and Adaptations

Study Guide - Practice Questions

Study Guide - Flashcards