Chapter 28

Question 1

The Italian physician who suggested that disease was caused by unseen organisms in 1546

Answer 1

Girolamo Fracatoro

Question 2

The first to observe and accurately describe microbial life

Answer 2

Anton van Leeuwenhoek

Question 3

French microbiologist who refuted the controversy over spontaneous generation

Answer 3

Louis Pasteur

Question 4

German physician who studied anthrax and was able to determine the causative agent

Answer 4

Robert Koch

Question 5

Koch’s postulates

1. The microorganism must be present in ____ and absent in ____
2. The causative agent must be ____
3. The same disease must result when ___
4. The same microorganisms must be ____

Answer 5

1. must be present in every case of the disease and absent in healthy individuals
2. Isolated and grown in a pure culture
3. When the cultured microorganism is used to infect a healthy host
4. Isolated again from the diseased host

Question 6

The oldest, structurally simplest, and most abundant forms of life. The only organisms with prokaryotic cellular organization.

Answer 6

Archaea and bacteria

Question 7

Unicellularity

Answer 7

Prokaryotes are fundamentally single celled

Question 8

In their natural environments most bacteria appear to be capable of forming a complex community of different species called a ___

Answer 8

Biofilm

Question 9

Cell size

Answer 9

Most prokaryotic cells are only 1 micrometer or less in diameter, they are very small

Question 10

Nucleoid

Answer 10

Prokaryotes lack a membrane bound nucleus and instead usually have a singular circular chromosome

Question 11

Flagella

Answer 11

Prokaryotic flagella are composed of a single fiber. Bacterial flagella are also more rigid and spin like a propellar

Question 12

Metabolic diversity

Answer 12

Prokaryotes are the only chemolithoautotrophic organisms meaning they use inorganic molecules to make carbohydrates

Question 13

Name the four key areas that Archaea and Bacteria differ

Answer 13

Plasma membranes
Cell wall
DNA replication
Gene expression

Question 14

Archaen plasma membrane lipids are composed of _____ linked to ______ by ether linkages, not the ester linkages seen in bacteria and eukaryotes

Answer 14

glycerol linked to hydrocarbon chains by ether linkages

Question 15

The cell wall of bacteria are constructed minimally of ___ which is formed from carbohydrate polymers linked together

Answer 15

Peptidoglycan

Question 16

The cell walls of archaea lack peptidoglycan although some have ____ which is similar in structure and function

Answer 16

Pseudomurein

Question 17

Archael initiation of DNA replication is similar to that of ___

Answer 17

eukaryotes

Question 18

In terms of gene expression, archaea may have more than one ____. Some of the translation machinery is also more similar to that of eukaryotes

Answer 18

RNA polymerase

Question 19

Molecular approaches to classification of Prokaryotes

1. the analysis of ______ of key proteins
2. The analysis of ____ by establishing a percent of G and C
3. ______ the mixing of single-stranded DNA from two species and determining the amount of base pairing
4. ___ and ____ sequencing, especially looking at ribosomal RNA
5. Whole ____ sequencing

Answer 19

1. the amino acid sequence of key proteins
2. nucleic acid-base sequences by establishing the percent of G and C
3. Nucleic acid hybridization
4. gene and RNA
5. genome

Question 20

Developed the three-domain system of phylogeny

Answer 20

Carl Woese

Question 21

The study of prokaryotic organisms was first made possible by

Answer 21

microscopes

Question 22

Early microbiology grew from the study of

Answer 22

disease-causing agents

Question 23

Bacteria and archaea are clearly different based on both ___ and ____

Answer 23

structure and metabolism

Question 24

Classification of prokaryotes had been based on ___ and it has now been aided by the use of ____

Answer 24

physical characteristics

DNA analysis

Question 25

A vast number of prokaryotes have not been studied because

Answer 25

they cannot be cultured

Question 26

Most prokaryotes exhibit one of the three basic shapes

Answer 26

bacilli, cocci, and spirals

Question 27

one or several of these structures may be found on the outer surface of many prokaryotes, used to propel the organisms in a fluid environment

Answer 27

Flagella

Question 28

Minimally the prokaryotic cell wall consists of ____ which is important for structure because it maintains the shape of the cell and prevents it from swelling and rupturing in hypotonic solutions

Answer 28

peptidoglycan

Question 29

Have a thick layer of peptidoglycan and stain a purple color

Answer 29

Gram-positive

Question 30

Contain less peptidoglycan and do not retain the purple dye. Can be stained with a red counter stain and then appear dark pink

Answer 30

Gram negative

Question 31

In some bacteria and archaea an additional protein layer forms a rigid paracrystalline surface called a _____. Often involves adhesion to surfaces or protections

Answer 31

S-layer

Question 32

In some bacteria an additional gelatinous layer called a ___ surrounds the other wall layers. Enables the cell to adhere to surfaces and other cells and to evade an immune response.

Answer 32

Capsule

Question 33

Other hairlike structures that occur on the cells of some gram-negative prokaryotes, they are more important in adhesion than in movement, they also play a role in the exchange of genetic information

Answer 33

pili

Question 34

Some prokaryotes are able to form a thick wall around their genome and a small portion of cytoplasm when they are exposed to environmental stress, When conditions improve they can germinate and return to normal cell division

Answer 34

Endospore

Question 35

Many prokaryotes possess invaginated regions of the plasma membrane that function in respiration or photosynthesis

Answer 35

Internal membranes

Question 36

Prokaryotes lack nuclei and generally do not possess linear chromosomes. Instead their genes are encoded in a single double stranded ring of DNA that is highly condensed to form a visible region of the cell called the

Answer 36

Nucleoid region

Question 37

Prokaryotic __ are smaller than those of eukaryotes and differ in protein and RNA content

Answer 37

ribosomes

Question 38

Horizontal gene transfer that occurs when genes move from one cell to another

Answer 38

conjugation

Question 39

Conjugation performed by viruses

Answer 39

transduction

Question 40

Some plasmids can be trasnferred from one cell to another via conjugation. The best known plasmid capable of transfer is

Answer 40

F plasmid or fertility factor

Question 41

Acts as an independent genetic entity that nevertheless depends on the cell for replicaiton

Answer 41

Plasmid

Question 42

When the F plasmid is integrated into the chromosome, the cell is called an

Answer 42

Hfr cell (high frequency of recombination)

Question 43

Genes close to the origin of transfer are transferred __ and this far from the origin are transferred ___

Answer 43

earlier | later

Question 44

Can be used to determine if new isolated mutations are alleles of known genes

Answer 44

Merodiploids

Question 45

The uptake of DNA directly from the environment

Answer 45

transformation

Question 46

Some conjugative plasmids pick up antibiotic resistance genes becoming

Answer 46

R plasmids

Question 47

DNA can be exchanged by conduction via ___ by transduction via ___ and by transformation through ___

Answer 47

plasmids viruses the direct uptake of DNA from the environment

Question 48

The different forms of DNA exchange can be used to

Answer 48

map genes

Question 49

Variation in prokaryotes also arises through

Answer 49

mutation

Question 50

Extensive use of antibiotics has led to selection for

Answer 50

resistant organisms

Question 51

Many bacteria carry out photosynthesis, using the energy of sunlight to build organic molecules from carbon dioxide. These are called ____

Answer 51

Photoautotrophs

Question 52

Some prokaryotes obtain energy by oxidizing inorganic substances and are called ____

Answer 52

chemolithoautotrophs | ex: nitrifiers

Question 53

Purple and green nonsulfur bacteria use light as a source of energy but obtain carbon from organic molecules produced by other organisms and are called

Answer 53

Photoheterotrophs

Question 54

The majority of prokaryotes obtain both carbon atoms and energy from organic molecules and are called

Answer 54

Chemoheterotrophs

Question 55

Some bacteria can attack other cells directly. The invading pathogen Yersinia (bubonic plague) secretes proteins that contain a special signal that allows them to pass through the bacterium's double membrane like a syringe and into the cytoplasm of host cells. This system is known as

Answer 55

Type III system

Question 56

Almost every kind of plant is susceptible to one or more kinds of bacterial disease including ___,____, and ____

Answer 56

blights soft rots wilts

Question 57

One of the oldest known infections. Afflicts the respiratory system and thwarts the immune system. Easily transmitted through the air

Answer 57

Tuberculosis

Question 58

What is the treatment for TB?

Answer 58

Multiple expensive ABX for 6-12 months

Question 59

Tooth decay is caused by the bacteria present in plaque

Answer 59

S. sobrinus and S. mutans

Question 60

Many STD's are caused by bacteria three important examples are

Answer 60

gonorrhea syphilis chlamydia

Question 61

Prokaryotes and fungi that carry out the decomposition portion of chemical cycles releasing a dead organism's atoms to the environment

Answer 61

Decomposers

Question 62

Prokaryotes that return elements from inorganic forms to organic forms that heterotrophic organisms can use

Answer 62

Fixation

Question 63

Plants, algae, and photosynthetic prokaryotes produce organic compounds from CO2. Are responsible for the oxygen in the earth's atmosphere

Answer 63

Carbon fixers

Question 64

A few species of prokaryotes are able to reduce nitrogen gas in the air into ammonia which is used to build amino acids

Answer 64

Nitrogen fixers

Question 65

In aquatic environments nitrogen fixation is carried out by ____. In soil it is carried out by ____

Answer 65

cyanobacteria/heterocysts | bacteria that live in the roots of plants

Question 66

Many bacteria live within the digestive tracts of animals providing nutrients to their hosts

Answer 66

mutualism

Question 67

Many bacteria inhabit outer surfaces of other animals ad plants without doing damage

Answer 67

Commensalism

Question 68

The use of organisms to remove pollutants from water, air, and soil Ex: breakdown of sewage by bacteria in sewage treatment plants, methane produced is harnessed for heat energy

Answer 68

bioremediation

Question 69

The addition of nutrients to encourage the growth of naturally occurring microbes that can degrade crude oil sills

Answer 69

Biostimulation