Biology

Mary Ann Clark, Jung Choi, Matthew Douglas

Chapter 22

Prokaryotes: Bacteria and Archaea - all with Video Answers

Educators

SR

Chapter Questions

Problem 1

Compared to free-floating bacteria, bacteria in biofilms often show increased resistance to antibiotics and detergents. Why do you think this might be the case?

Tate Hilken

Tate Hilken

Numerade Educator

Problem 2

Which of the following statements is true?
a. Gram-positive bacteria have a single cell wall anchored to the cell membrane by lipoteichoic acid.
b. Porins allow entry of substances into both Gram-positive and Gram-negative bacteria.
c. The cell wall of Gram-negative bacteria is thick, and the cell wall of Gram-positive bacteria is thin.
d. Gram-negative bacteria have a cell wall made of peptidoglycan, whereas Grampositive bacteria have a cell wall made of lipoteichoic acid.

Tate Hilken

Numerade Educator

Problem 3

Which of the following statements about the nitrogen cycle is false?
a. Nitrogen fixing bacteria exist on the root nodules of legumes and in the soil.
b. Denitrifying bacteria convert nitrates (NO3) into nitrogen gas ( $\mathrm{N}_{2}$ ).
c. Ammonification is the process by which ammonium ion $\left(\mathrm{NH}_{4}^{+}\right)$ is released from decomposing organic compounds.
d. Nitrification is the process by which nitrites (NO2) are converted to ammonium ion. $\left(\mathrm{NH}_{4}^{+}\right).$

Tate Hilken

Numerade Educator

Problem 4

The first forms of life on Earth were thought to be __________ .
a. single-celled plants
b. prokaryotes
c. insects
d. large animals such as dinosaurs

Tate Hilken

Numerade Educator

Problem 5

Microbial mats __________.
a. are the earliest forms of life on Earth
b. obtained their energy and food from hydrothermal vents
c. are multi-layered sheets of prokaryotes including mostly bacteria but also archaea
d. all of the above

Tate Hilken

Numerade Educator

Problem 6

The first organisms that oxygenated the atmosphere were
a. cyanobacteria
b. phototrophic organisms
c. anaerobic organisms
d. all of the above

Tate Hilken

Numerade Educator

Problem 7

Halophiles are organisms that require __________.
a. a salt concentration of at least $0.2 \mathrm{M}$
b. high sugar concentration
c. the addition of halogens
d. all of the above

Tate Hilken

Numerade Educator

Problem 8

Many of the first prokaryotes to be cultured in a Scientific lab were human or animal pathogens. Why would these species be more readily cultured than non-pathogenic prokaryotes?
a. Pathogenic prokaryotes are hardier than non-pathogenic prokaryotes.
b. Non-pathogenic prokaryotes require more supplements in their growth media.
c. Most of the necessary culture conditions could be inferred for pathogenic prokaryotes.
d. Pathogenic bacteria can grow as free bacteria, but non-pathogenic bacteria only grow as parts of large colonies.

Dr. Anas Syed

Numerade Educator

Problem 9

The presence of a membrane-enclosed nucleus is a characteristic of __________ .
a. Pathogenic prokaryotes are hardier than non-pathogenic prokaryotes.
b. Non-pathogenic prokaryotes require more supplements in their growth media.
c. Most of the necessary culture conditions could be inferred for pathogenic prokaryotes.
d. Pathogenic bacteria can grow as free bacteria, but non-pathogenic bacteria only grow as parts of large colonies.

Glyniss A

Numerade Educator

Problem 10

Which of the following consist of prokaryotic cells?
a. bacteria and fungi
b. archaea and fungi
c. protists and animals
d. bacteria and archaea

Tate Hilken

Numerade Educator

Problem 11

The cell wall is __________ .
a. interior to the cell membrane
b. exterior to the cell membrane
c. a part of the cell membrane
d. interior or exterior, depending on the
particular cell

Tate Hilken

Numerade Educator

Problem 12

Organisms most likely to be found in extreme environments are __________ .
a. fungi
b. bacteria
c. viruses
d. archaea

Tate Hilken

Numerade Educator

Problem 13

Prokaryotes stain as Gram-positive or Gramnegative because of differences in the cell __________ .
a. wall
b. cytoplasm
c. nucleus
d. chromosome

Tate Hilken

Numerade Educator

Problem 14

Pseudopeptidoglycan is a characteristic of the walls of __________ .
a. eukaryotic cells
b. bacterial prokaryotic cells
c. archaean prokaryotic cells
d. bacterial and archaean prokaryotic cells

Tate Hilken

Numerade Educator

Problem 15

The lipopolysaccharide layer (LPS) is a characteristic of the wall of __________ .
a. archaean cells
b. Gram-negative bacteria
c. bacterial prokaryotic cells
d. eukaryotic cells

Tate Hilken

Numerade Educator

Problem 16

Which of the following elements is not a micronutrient?
a. boron
b. calcium
c. chromium
d. manganese

Caroline Jones

Numerade Educator

Problem 17

Prokaryotes that obtain their energy from chemical compounds are called __________ .
a. phototrophs
b. auxotrophs
c. chemotrophs
d. lithotrophs

Tate Hilken

Numerade Educator

Problem 18

Ammonification is the process by which __________ .
a. ammonia is released during the decomposition of nitrogen-containing organic compounds
b. ammonium is converted to nitrite and nitrate in Soils
c. nitrate from soil is transformed to gaseous nitrogen compounds such as $\mathrm{NO}, \mathrm{N}_{2} \mathrm{O},$ and $\mathrm{N}_{2}$
d. gaseous nitrogen is fixed to yield ammonia

Tate Hilken

Numerade Educator

Problem 19

Plants use carbon dioxide from the air and are therefore called __________ .
a. consumers
b. producers
c. decomposer
d. carbon fixers

Tate Hilken

Numerade Educator

Problem 20

Cyanobacteria harness energy from the sun through photosynthesis, and oxidize water to provide electrons for energy generation. Thus, we classify cyanobacteria as _________.
a. photolithotrophs
b. photoautotrophs
c. chemolithoautotrophs
d. chemo-organotrophs

Tate Hilken

Numerade Educator

Problem 21

A disease that is constantly present in a population is called _____.
a. pandemic
b. epidemic
c. endemic
d. re-emerging

Tate Hilken

Numerade Educator

Problem 22

Which of the statements about biofilms is incorrect?
a. Biofims are considered responsible for diseases such as cystic fibrosis.
b. Biofims produce dental plaque, and colonize catheters and prostheses.
c. Biofilms colonize open wounds and burned tissue.
d. All statements are incorrect.

Jared Adelman

Numerade Educator

Problem 23

Which of these statements is true?
a. An antibiotic is any substance produced by
a organism that is antagonistic to the growth of prokaryotes.
b. An antibiotic is any substance produced by a prokaryote that is antagonistic to the growth of other viruses.
c. An antibiotic is any substance produced by
a prokaryote that is antagonistic to the growth of eukaryotic cells.
d. An antibiotic is any substance produced by
a prokaryote that prevents growth of the Same prokaryote.

Joanna Quigley

Numerade Educator

Problem 24

A person in England arrives at a medical clinic with a fever and swollen lymph nodes shortly after returning from a visit to New Mexico. For which bacteria should the doctor test the patient?
a. Salmonella enterica
b. Borrelia burgdorferi
c. Clostridium botulinum
d. Yersinia pestis

Tate Hilken

Numerade Educator

Problem 25

MRSA has emerged as a serious infectious disease, with the first case of methicillin-resistant S. aureus being detected in $1961 .$ Why are medical professionals so concerned when antibiotics exist that can kill MRSA?
a. MRSA can transfer methicillin-resistance to other bacteria.
b. Patients are not treated with correct antibiotics rapidly enough to prevent serious illness.
c. MRSA could acquire additional antibiotic resistance genes from other bacteria to become a "super bug."
d. All of the above.

Joanna Quigley

Numerade Educator

Problem 26

Which of these occurs through symbiotic nitrogen fixation?
a. The plant benefits from using an endless source of nitrogen.
b. The soil benefits from being naturally fertilized.
c. Bacteria benefit from using photosynthates from the plant.
d. All of the above occur.

Leah Lampen

Numerade Educator

Problem 27

Synthetic compounds found in an organism but not normally produced or expected to be present in
that organism are called _____.
a. pesticides
b. bioremediators
c. recalcitrant compounds
d. xenobiotics

Dading Chen

Numerade Educator

Problem 28

Bioremediation includes _____.
a. the use of prokaryotes that can fix nitrogen
b. the use of prokaryotes to clean up pollutants
c. the use of prokaryotes as natural fertilizers
d. All of the above

Tate Hilken

Numerade Educator

Problem 29

In addition to providing yogurt with its unique flavor and texture, lactic acid-producing bacteria also provide which additional benefit during food production?
a. Providing xenobiotics
b. Lowering the pH to kill pathogenic bacteria
c. Pasteurizing milk products
d. Breaking down lactose for lactose-intolerant individuals

Tate Hilken

Numerade Educator

Problem 30

Describe briefly how you would detect the presence of a non-culturable prokaryote in an environmental sample.

Tate Hilken

Numerade Educator

Problem 31

Why do scientists believe that the first organisms on Earth were extremophiles?

Tate Hilken

Numerade Educator

Problem 32

A new bacterial species is discovered and classified as an endolith, an extremophile that lives inside rock. If the bacteria were discovered in the permafrost of Antarctica, describe two extremophile features the bacteria must possess.

Tate Hilken

Numerade Educator

Problem 33

Mention three differences between bacteria and archaea.

Joanna Quigley

Numerade Educator

Problem 34

Explain the statement that both types, bacteria and archaea, have the same basic structures, but built from different chemical components.

Joanna Quigley

Numerade Educator

Problem 35

A scientist isolates a new species of prokaryote. He notes that the specimen is a bacillus with a lipid bilayer and cell wall that stains positive for peptidoglycan. Its circular chromosome replicates from a single origin of replication. Is the specimen most likely an Archaea, a Gram-positive bacterium, or a Gram-negative bacterium? How do you know?

Joanna Quigley

Numerade Educator

Problem 36

Think about the conditions (temperature, light, pressure, and organic and inorganic materials) that you may find in a deep-sea hydrothermal vent. What type of prokaryotes, in terms of their metabolic needs (autotrophs, phototrophs, chemotrophs, etc.), would you expect to find there?

Tate Hilken

Numerade Educator

Problem 37

Farmers continually rotate the crops grown in different fields to maintain nutrients in the soil. How would planting soybeans in a field the year after the field was used to grow carrots help maintain nitrogen in the soil?

Tate Hilken

Numerade Educator

Problem 38

Imagine a region of soil became contaminated, killing bacteria that decompose dead plants and animals. How would this effect the carbon cycle in the area? Be specific in stating where carbon would accumulate in the cycle.

Courtney Burson

Courtney Burson

Numerade Educator

Problem 39

Explain the reason why the imprudent and excessive use of antibiotics has resulted in a major global problem.

Victoria Karaluz

Victoria Karaluz

Numerade Educator

Problem 40

Researchers have discovered that washing spinach with water several times does not prevent foodborne diseases due to E. coli. How can you explain this fact?

Tate Hilken

Numerade Educator

Problem 41

Your friend believes that prokaryotes are always detrimental and pathogenic. How would you explain to them that they are wrong?

Tate Hilken

Numerade Educator

Problem 42

Many people use antimicrobial soap to kill bacteria on their hands. However, overuse may actually increase the risk of infection. How could this occur?

Tate Hilken

Numerade Educator