Alcamo's Fundamentals Of Microbiology Chapter 5

Front 1

What bacteria had the ability to grow in an enviroment consistant with that of Mars?

Back 1

Archaea especially the methanogens

Front 2

what is an extremophile?

Back 2

organisms that survive and even require living in an extreme enviroment

Front 3

asexual reproduction is ______

Back 3

the form of reproduction that maintains genetic constancy while increasing cell numbers

Front 4

Binary Fission

Back 4

the act of a cell splitting itself into two identical cells after a period in which the cell has doubled in mass

Front 5

How do most bacterial organisms reproduce?

Back 5

Binary Fission

Front 6

What are the four steps in the binary fission process

Back 6

1. cell elongates and DNA is replicated
2. cell wall and cell membrane begin to invaginaten(fission ring appears)
3. cross wall forms two distinct cells
4. cells separate

Front 7

Bacterial cells lack a ___________ ____________ to separate replicated chromosomes.

Back 7

mitotic spindle

Front 8

Whay is it thought that reproduction by binary fission confers immortality?

Back 8

there is never a moment at which the first bacterial cell has died

Front 9

Generation time

Back 9

the interval of time between sucessive binary fissions of a cell or population of cells

Front 10

Incubation Period

Back 10

the time from entry of a pathogen into the body until the first symptoms appear

Front 11

If the division time of a cell is faster, what happens to the incubation period?

Back 11

It is shorter and the symptoms appear quickly

Front 12

What will halt the progress of cell reproduction?

Back 12

depletion of food or buildup of waste

Front 13

Bacterial growth curve

Back 13

illustration of the bacterial growth events over time

Front 14

What happens during the lag phase?

Back 14

NO CELL DIVISION. bacterial cells are adapting to their new enviroment.
**Some die from scaveging WBC'c, shock of transfer or the inability to adapt.
**The remaining cells must grow in size, store nutrients and synthesize essential enzymes

Front 15

What happens during the Log (logarythmic) Phase?

Back 15

Exponential growth phase
**ALL cells are undergoing binary fission
**Disease symptoms usually develop ebcause the bacterial cells are causing tissue damage
**highest vulnerability to antibiotics

Front 16

What happens during the stationary phase?

Back 16

Reproductive and death rates equalize and the population enters a PLATEAU
**in the body: antibodies and WBC's are attacking and destructing the bacteria
**in the test tube: nutrients become scarce, waste products build and oxygen supplies are short

Front 17

What happens in the decline phase?

Back 17

the number of dying cells outnumber the new cells formed
**glycocalyx (capsule) may forestall death by acting as a buffer to the enviroment, and flagella may enabke organisms to move to a new enviroment

Front 18

Some bacterial species can escape cell death by forming ___________.

Back 18

endospores

Front 19

What two gram positive bacterial species are known for producing highly resistant endospores?

Back 19

Bacillus and Clostridium

Front 20

When does sporulation begin?

Back 20

when the bacterial chromosome replicates and binary fission is characterized by an assymetrical cell divisiion. The smaller cell, the prespore, will become the endospore

Front 21

IS sporulation a reproductive process

Back 21

NO this is a dormant phase in the life of the bacterial species

Front 22

What causes the endospores to be resilient to heat and undergo very few chemical reactions.

Back 22

minimal water

Front 23

2 hours

Back 23

How long can endospores remain in boiling water

Front 24

When do the protective layers of the endospores break down and germinate into a vegitative cell

Back 24

when the emviroment is favorable

Front 25

What is the bacteria that causes anthrax

Back 25

Bacillius Anthracis

Front 26

What is the bacteria that causes botulism, gas gangrene and tetnus

Back 26

Clostridium

Front 27

Where does Anthrax germinate?

Back 27

in the lower respiratory tract

Front 28

WHat type of enviroment do clostridium cells need to germinate?

Back 28

oxygenn free enviroment.

Front 29

What method has shown to be the most effective at kiling endospores?

Back 29

heating them at high pressures for many hours

Front 30

What can kill a newly germinated endospore before the vegitative cell can produce and secrete deadly toxins?

Back 30

Antibiotics

Front 31

What physical factors need to be optimal for microbial growth?

Back 31

Temperature
pH
Oxygen gas

Front 32

Psychrophiles

Back 32

microbes that have their optimal growth rates in 15 degrees celcius but can still grow at 0-20 degrees celcius

Front 33

Psychrotrophs are most likely to be found where?

Back 33

In s refrigerated enviroment on spoiled foods

Front 34

When foods that are consumed without heating , the toxins may cause food poisoning. What is an example of a commonly encountered bacteria that causes diarrhea.

Back 34

campylobacter

Front 35

Thermophiles

Back 35

bacteria that multiply best at higher temperatures. Their optimal enviroment is tempersture id sround 60 degrees celcius but can multiply in a range from 40-70 degrees celcius

Front 36

Why are thermophiles important to be aware of in dairy production

Back 36

They survive the pasteurization temperatures

Front 37

Mesophiles

Back 37

bacgterial which thrive in the middle region of temperatures ranging from 10-45 degrees celcius

Front 38

Obligate anerobes must use oxygen as what?

Back 38

a final electron acceptor to make cellular energy

Front 39

Microaerophiles

Back 39

species that can survive in concentrations of relatively low oxygen

** Trapenemo pallidum- syphillus

Front 40

Anerobes

Back 40

bacteria that do not and can not use oxygen

Front 41

aerotolerant

Back 41

anerobes that are insensitive to oxygen

Front 42

obligate anerobes

Back 42

bacteria that are killed or inhibited by the presence of oxygen

Front 43

What chemical do obligate anerobes use in their metabolic processes and what is the waste product.

Back 43

they use sulfur and the waste product is hydrogen sulfide

Front 44

What is a facultative microbe?

Back 44

One that is neither aerobic or anerobic. It can grow in either the presence or a reduce concentration of oxygen

Front 45

how do facultative anerones and aerobes differ from regular anerobes and aerobes.

Back 45

facultative aerobes prefers anerobic conditions while a facultative anerobes prefers aerobic conditions.

Front 46

Most microbes have a pH near _____.

Back 46

7.0

Front 47

Acidophiles

Back 47

Acid-tolerant bacteria

Front 48

Extreme acidophiles

Back 48

acidophiles that grow in extremely acidic enviroments

Front 49

Barophiles

Back 49

Bacteria that can survive in enviroments with high hydrostatic pressure

Front 50

nonhalophiles

Back 50

microbes that are unable to grow in the presence of salt

hence using salt as a preservative

Front 51

halotolerant

Back 51

microbes that grow best without salt but are able to tolerate low concentrations of it

Front 52

halophiles

Back 52

microbes that require salt to survive

Front 53

extreme halophile

Back 53

microbes that tolerate high concentrations of salt

Front 54

Agar is a polysaccharide derived from what?

Back 54

red marine algea

Front 55

colloid

Back 55

aggregate of molecules in a finely divided state dispersed in a solid medium

Front 56

Agar remains liquid until it is cooled to below approximately ________.

Back 56

36 degrees celcius

Front 57

complex medium contains?

Back 57

nutrients in which the exact components or their quantities are not known.

Front 58

synthetic medium contains?

Back 58

nutrients in which the precise chemical composition and amount of all components are known

Front 59

selective medium contains?

Back 59

ingredients to inhibit the growth of cretain microbes in a mixture while allowing the growth of others.

Front 60

differential medium

Back 60

contains specific chemicals to indicate which particular species possess and which lack a particular biochemical process

Front 61

fastidious organisms

Back 61

having a complex nutritional requirement. Uses enriched medium that contains special nutrients.