Topic 1 Check Your Understanding

Question 1

What are some of the destructive actions of microbes?

Answer 1

food spoilage and cause of disease

Question 2

What are some of the beneficial actions of microbes?

Answer 2

break down waste, treat sewage, control pests
food, chemical, and drug production
human microbe: aid in digestion, synthesize vitamins, train immune system

Question 3

Who developed the identification used in microbiology today?

Answer 3

Carolus Linnaeus in 1735

Question 4

What is a genus?

Answer 4

the first part of a scientific name; identifies the genus (generic name) which the species belongs to; always capitalized

Question 5

What is a specific epithet?

Answer 5

the second part of a scientific name; identifies the specific name and distinguishes the species within the genus; always lowercase

Question 6

What microbes are prokaryotes?

Answer 6

bacteria and archae

Question 7

Describe bacteria

Answer 7

• shapes include bacillus (rodlike), coccus (spherical), and spiral
• cell walls have peptidoglycan
• reproduce via binary fission
• movement via flagells

Question 8

Describe archae

Answer 8

• cell walls have NO peptidoglycan
• live in extreme environments
• three types: methanogens, extreme halophiles (salty), extreme thermophiles

Question 9

What microbes are eukaryotes?

Answer 9

fungi, protozoa, algea

Question 10

Describe fungi

Answer 10

• cell walls made of chitin
• can be unicellular or multicellular
• size is larger than bacteria

Question 11

Describe protozoa

Answer 11

• unicellular
• move via flagella, pseudopods, or chillia

Question 12

Describe algaw

Answer 12

• photosynthetic
• cell wall is made of cellulose

Question 13

Describe viruses

Answer 13

• acellular
• very, very small
• simple structure: core made of RNA or DNA surrounded by a protein coat
• reproduce only by using the cellular machinery of other organisms

Question 14

What are the three domains of life?

Answer 14

bacteria, archaea, and eukarya

Question 15

What is one of the early instances of ancient microbiology?

Answer 15

prehistoric people took advantage of fermentation to preserve and enhance the taste of food

Question 16

What contributions did the ancient greeks make to microbiology?

Answer 16

attributed disease to bad air; developed hygiene practices built on this idea

Question 17

What contributions did the ancient romans make to microbiology?

Answer 17

believed in the miasma hypothesis; built complex waste management infrastructure

Question 18

What contributions did Hippocrates make to microbiology?

Answer 18

father of western medicine (460 BCE), believed that diseases had natural causes from within patients or their environments

Question 19

What contributions did Thucydides make to microbiology?

Answer 19

father of scientific history (460 BCE), advocated for evidence based analysis of cause-and-effect reasoning

Question 20

What contributions did Varro make to microbiology?

Answer 20

27 BCE, proposed the concept that things we cannot see can cause disease

Question 21

What is cell theory?

Answer 21

the theory that all living things are composed of cells

Question 22

How was cell theory established?

Answer 22

1. Hooke (1665) observed the existence of cells
2. van Leeuwenhoek (1668) was the first to observe live microorganisms using a magnifying lens

Question 23

What is spontaneous generation?

Answer 23

the belief that some forms of life could arise spontaneously from nonliving matter

Question 24

What is biogeniss?

Answer 24

a challenge to spontaneous generation developed by Rudolg Virchose (1855), hypothesized that living cells arise only from preexisting living cells

Question 25

Describe the contributions of Redi towards the belief in spontaneous generation.

Answer 25

demonstrated that maggots did not arise spontaneously; though smaller organisms could still generate from nonliving matter

Question 26

Describe the contributions of Needham towards the belief in spontaneous generation.

Answer 26

heated brother and poured it into covered flasks; observed microbes developing spontaneously from the fluids

Question 27

Describe the contributions of Spallanzani towards the belief in spontaneous generation.

Answer 27

suggested that microorganisms from the air likely entered Needham's solutions after they were boiled

Question 28

Describe the contributions of Pasteur towards the belief in spontaneous generation.

Answer 28

proved that microorganisms are present in the air and can contaminate sterile solutions, but that the air itself does not create microbes

Question 29

What is the germ theory of disease?

Answer 29

the belief that microorganisms, to small to be seen with the naked eye, can invade living organisms and cause disease

Question 30

How was the germ theory of disease developed?

Answer 30

- Pasteur (1857) discovered that yeasts play a crucial role in fermentation; first link between the activity of microorganisms and physical/chemical changes in organic materials - Pasteur, Koch, and Lister all made contributions towards the germ theory of disease

Question 31

What did Koch discover?

Answer 31

In 1876, established the first proof that bacteria can cause specific disease and can be isolated and cultured on artificial media

Question 32

What are koch's postulates?

Answer 32

a sequence of experimental steps for directly relating a specific microbe to a specific disease

Question 33

What are the four koch's postulates?

Answer 33

1. the same pathogen must be present in every case of the disease 2. the pathogen must be isolated from the diseases host and grown in pure culture 3. the pathogen from the pure culture must cause the disease when it's inoculated into a healthy, susceptible laboratory animal 4. the pathogen must be isolated from the inoculated animal and must be be shown to be in the original organisms

Question 34

What is the significance of Jenner's discovery?

Answer 34

1796, experimented to figure out way to protect people from smallpox via vaccination with cowpox

Question 35

Describe the other contributions of Pasteur to microbiology.

Answer 35

- fermentation: found that microorganisms called yeasts can convert sugar to alcohol in the absence of air; process is used to make wine and beer - pasteurization: developed the process for heating liquids just enough to kill most bacteria to prevent disease and spoilage - discovered why vaccinations work through work with chicken cholera; introduced the concept that vaccination could be applied to any microbial disease