Microbiology Chapter 1.1 & 1.2

Question 1

By definition, what are microbes?

Answer 1

Very small organisms

Question 2

Microbes are also referred to as what?

Answer 2

Microorganisms or “germs”

Question 3

By definition, what is microbial fermentation?

Answer 3

A process that uses bacteria, mold, or yeast to convert sugars (carbohydrates) to alcohol, gases, and organic acids

Question 4

The power of fermentation made foods like what? Using what? Give 3 examples.

Answer 4

Bread, cheese, and wine, using microbial fermentation

Question 5

Can you see microbes with the naked eye?

Answer 5

No. Many types of microbes are too small to see without a microscope, although some parasites and fungi are visible to the naked eye

Question 6

By definition, what is yeast?

Answer 6

Yeast is a microorganism. Its cells metabolize the carbohydrates in flour (middle) and produce carbon dioxide, which causes the bread to rise

Question 7

What is the name of the yeast responsible for making bread rise?

Answer 7

Saccharomyces cerevisiae

Question 8

The ancient Greeks attributed disease to what?

Answer 8

Bad air, mal’aria, which they called “miasmatic odors.” They developed hygiene practices that built on this idea.

Question 9

How did the Romans combat the illnesses created by microbes during prehistoric times?

Answer 9

In Rome, they built aqueducts, which brought fresh water into the city, and a giant sewer, the Cloaca Maxima, which carried waste away and into the river Tiber

Question 10

What are the affects of microbes?

Answer 10

They can cause infection, disease, and death

Question 11

The Greek physician Hippocrates is considered what?

Answer 11

The “father of Western medicine”

Question 12

When was the existence of microbes confirmed?

Answer 12

After the invention of the microscope

Question 13

When was the “Golden Age of Microbiology”?

Answer 13

Discoveries between 1857 and 1914.

Question 14

Much of what we know about human cells comes from what?

Answer 14

Our understanding of microbes

Question 15

Are microbes diverse or constricted?

Answer 15

Microbes are enormously diverse

Question 16

How can microorganisms vary?

Answer 16

Microorganisms vary in all sorts of ways, including their size, their appearance, and their rates of reproduction.

Question 17

By definition, what is taxonomy?

Answer 17

Taxonomy is the classification, description, identification, and naming of living organisms.

Question 18

By definition, what is classification?

Answer 18

Classification is the practice of organizing organisms into different groups based on their shared characteristics.

Question 19

Who published Systema Naturae, an 11-page booklet in which he proposed the Linnaean taxonomy?

Answer 19

Botanist, zoologist, and physician named Carolus Linnaeus

Question 20

By definition, what is Linnaean taxonomy?

Answer 20

A system of categorizing and naming organisms using a standard format so scientists could discuss organisms using consistent terminology

Question 21

With advances in technology, other scientists gradually made refinements to the Linnaean system and eventually created new systems for classifying organisms.

Answer 21

Fun Fact

Question 22

By definition, what are phylogonies? & how are they depicted?

Answer 22

Evolutionary relationships of all different species of organisms on earth; They are depicted via a diagram called a phylogenetic tree (or tree of life)

Question 23

How can one depict relationships in the phylogenetic tree?

Answer 23

Via a diagram where groups of organisms are arranged by how closely related they are thought to be

Question 24

How were organisms grouped in early phylogenetic trees compared to how they are grouped now?

Answer 24

In early phylogenetic trees, the relatedness of organisms was inferred by their visible similarities, such as the presence or absence of hair or the number of limbs. Today, phylogenic analyses include genetic, biochemical, and embryological comparisons, as will be discussed later in this chapter

Question 25

How many branches did Linnaeus’s tree of life contain?

Answer 25

Just two main branches for all living things: the animal and plant kingdoms

Question 26

What 2 scientists proposed a new kingdom to the phylogenetic tree? & what kingdoms were they?

Answer 26

In 1866, Ernst Haeckel, proposed the kingdom Protista, for unicellular organisms He later proposed a fourth kingdom, Monera, for unicellular organisms whose cells lack nuclei, like bacteria.
Nearly 100 years later, in 1969, American ecologist Robert Whittaker proposed adding another kingdom—Fungi—in his tree of life.

Question 27

What was Whittakers 2nd contribution to the phylogenetic tree?

Answer 27

Whittaker’s tree also contained a level of categorization above the kingdom level—the empire or superkingdom level—to distinguish between organisms that have membrane-bound nuclei in their cells (eukaryotes) and those that do not (prokaryotes).

Question 28

What kingdom(s) does Empire Prokaryota contain?

Answer 28

Just the Kingdom Monera.

Question 29

What kingdom(s) does Empire Eukaryota contain?

Answer 29

The Empire Eukaryota contains the other four kingdoms: Fungi, Protista, Plantae, and Animalia.

Question 30

Are viruses contained in the phylogenetic tree?

Answer 30

No because they are not made up of cells and thus it is difficult to determine where they would fit into a tree of life.

Question 31

Describe the difference in how organisms are described and categorized in phylogenetic trees today compared to how Whittaker and Heckel described and categorized them in phylogenetic trees in the past?

Answer 31

Modern taxonomy relies heavily on comparing the nucleic acids (deoxyribonucleic acid [DNA] or ribonucleic acid [RNA]) or proteins from different organisms. The more similar the nucleic acids and proteins are between two organisms, the more closely related they are considered to be. Haeckel’s and Whittaker’s trees presented hypotheses about the phylogeny of different organisms based on readily observable characteristics.

Question 32

What role does genetics play in modern Taxonomy?

Answer 32

Genetic methods allow for a standardized way to compare all living organisms without relying on observable characteristics that can often be subjective.

Question 33

Carl Woese and George Fox created a genetics-based tree of life based on similarities and differences they observed in the gene sequences coding for small subunit ribosomal RNA (rRNA) of different organisms. In the process, they discovered that a certain type of bacteria, called archaebacteria (now known simply as Archaea), were significantly different from other bacteria and eukaryotes in terms of their small subunit rRNA gene sequences.

Answer 33

Fun Fact

Question 34

What domains above the level of Kingdom: did Carl Woese create?

Answer 34

Archaea, Bacteria, and Eukarya

Question 35

Who created binomial nomenclature?

Answer 35

Carolus Linnaeus

Question 36

By definition, what is a binomial nomenclature?

Answer 36

a two-word naming system for identifying organisms by genus and specific epithet. For example, modern humans are in the genus Homo and have the specific epithet name sapiens, so their scientific name in binomial nomenclature is Homo sapiens

Question 37

In binomial nomenclature, what is capitalized and what is not? Describe how binomial nomenclature is set up.

Answer 37

In binomial nomenclature, the genus part of the name is always capitalized; it is followed by the specific epithet name, which is not capitalized. Both names are italicized

Question 38

How are microorganisms named?What do there names reflect?

Answer 38

Today, newly discovered organisms can be given names derived from Latin, Greek, or English. Sometimes these names reflect some distinctive trait of the organism; in other cases, microorganisms are named after the scientists who discovered them

Question 39

In binomial nomenclature, what is the first part of the name called?

Answer 39

Genus

Question 40

In binomial nomenclature, what is the second part of the name?

Answer 40

Epithet

Question 41

Can microbes be difficult to identify? Why or why not?

Answer 41

Yes; Because so many bacteria look identical. Without easily observable macroscopic features like feathers, feet, or fur, scientists must capture, grow, and devise ways to study their biochemical properties to differentiate and classify microbes

Question 42

By definition, what is is the Bergey’s Manual?

Answer 42

Bergey’s Manual has the standard references for identifying and classifying different prokaryotes.Because so many bacteria look identical, methods based on nonvisual characteristics must be used to identify them.

Question 43

What are different testing method scientists can use to name and categorize organisms?

Answer 43

Biochemical tests can be used to identify chemicals unique to certain species
Serological tests can be used to identify specific antibodies that will react against the proteins found in certain species
DNA and rRNA sequencing can be used both for identifying a particular bacterial species and for classifying newly discovered species