Chapter 11: Microbes: Secret Lives of Single Cells

Question 1

Microbes

Answer 1

Small life, single cell, microscopic organisms

Question 2

Microbes Steps

Answer 2

1) The most abundant organisms on earth
2) Huge genetic diversity
3) Highly adaptive, exist in extremely hostile environments (temp, chemical, pressure)

Question 3

For every human cell in your body there may be

Answer 3

10 microbial cells

Question 4

What are microbes

Answer 4

1) Found in all 3 domains (bacteria, archaea and eukarya)
2) Minimal evolutionary relatedness
3) Viruses are not currently classified as living, but are microbes

Question 5

All bacteria and archaea members are

Answer 5

Microbes

Question 6

All eukaryotic microbes are known as

Answer 6

Protists

Question 7

Bacteria

Answer 7

Simplest organisms alive; cell membrane, cytoplasm, some proteins and genetic material

Question 8

Bacteria categorized by shape:

Answer 8

1) Bacillus (rod)
2) Coccus (round)
3) Spirillum (spiral)

Question 9

Bacteria categorized by Gram staining

Answer 9

1) Negative (penicillin-resistant)
2) Positive (penicillin-susceptible)

Question 10

Colonies of different bacterial types have

Answer 10

Different physical appearances

Question 11

Reproduce asexually via

Answer 11

Binary fission (cloning)

Question 12

Genetic exchange possible

Answer 12

1) Conjugation: exchanging DNA with another cell of the same species
2) Transduction: gaining DNA from viral capsid
3) Transformation: Scrouning for DNA

Question 13

Metabolism

Answer 13

Bacteria can get energy from many sources:
1) Chemoorganotrophs
2) Chemolithotrophs
3) Photoautotrophs

Question 14

Chemoorganotrophs

Answer 14

Eat organic molecules

Question 15

Chemolithotrophs

Answer 15

Eat inorganic molecules

Question 16

Photoautotrophs

Answer 16

Synthesize energy from sunlight (photosynthesis) (responsible for oxygen in earth’s early atmosphere)

Question 17

1) Bacteria can be useful:

Answer 17

1) Used in food production (yogurt, cheese, bread, etc.)
2) Used in food digestion (mircobes are capable of breaking down cellulose)
3) Normal (relatively harmless) flora coat your entire body, preventing the growth of harmful colonies

Question 18

Bacteria can be harmful:

Answer 18

1) Pathogenic organisms
2) Antibiotic resistance

Question 19

Pathogenic organisms causes

Answer 19

Disease

Question 20

Not all pathogens are always

Answer 20

Harmful, and many are normally benign, but under certain circumstances become pathogenic

Question 21

Antibiotic resistance

Answer 21

The process of bacteria evolving to survive exposure to antibiotics (penicillin initially was a highly effective antibiotic, but is now rarely used due to increased resistance)

Question 22

Archaea

Answer 22

Although outwardly similar to bacteria, archaea are dramatically different genetically

Question 23

Many archaea (along with some bacteria) are found in

Answer 23

Extreme environement (extremophiles)

Question 24

Archaea also thrive in

Answer 24

Less extreme environment, such as your gut

Question 25

Because archaea can survive in

Answer 25

Unusual environements, they may be useful to humans

Question 26

Enzymes from extremophiles function at

Answer 26

Higher or lower temperatures ranges

Question 27

Organisms that can metabolize toxic or hazardous materials can help

Answer 27

Dispose of waste or clean up spills

Question 28

Study organisms for

Answer 28

Outer space/colonizing research

Question 29

Viruses technically not living organisms:

Answer 29

Viruses (outside host: virion) are protein coated genetic material contained in capsids, not cells, sometimes with a few enzymes

Question 30

If host cell is a bacteria virus is a

Answer 30

Bacteriaphege

Question 31

Viral life cycle

Answer 31

1) Viral genome enters host cell
2) Viral genome is replicated and transcribed
3) Viral mRNAs are transmitted and proteins processed
4) Particle assemble inside host, then burst or bud to exterior

Question 32

Viruses can cause

Answer 32

Many harmful diseases, including the common cold, the flu (influenza), rabies and HIV/AIDS

Question 33

Viral diseases are categorized by

Answer 33

Genetic material like RNA or DNA-based

Question 34

DNA viruses do not evolve particularly quickly due to

Answer 34

The many DNA checkpoints in the replication process

Question 35

RNA viruses can evolve very quickly due to

Answer 35

The lack of checking mechanisms in RNA replication

Question 36

Influenza caused by an

Answer 36

RNA virus

Question 37

Influenza possible to have

Answer 37

Multiple flu viruses enter a single cell, including those that infect different species

Question 38

Influenza can get strains that incorporate

Answer 38

Multiple species surface proteins and thus infect multiple species as seen in swine or bird flu

Question 39

Large outbreaks of disease can lead to

Answer 39

Pandemic such as the Spanish flu of 1918

Question 40

HIV/AIDS

Answer 40

Although an RNA based virus, HIV is also retrovirus

Question 41

HIV/Retrovirus contains

Answer 41

Reverse transcriptase, allowing synthesis of DNA from RNA to be inserted into the hosts DNA

Question 42

HIV/AIDS highly prone to errors in

Answer 42

Transcription, leading to enormous variation in each new generation (many new mutations)

Question 43

HIV/AIDS once inserted, HIV targets the immune system mutating to

Answer 43

Gain access to the white blood cells that attack it

Question 44

Once a suitable mutation occurs HIV develops into

Answer 44

AIDS

Question 45

AIDS infections are characterized by

Answer 45

A collapse of the immune system

Question 46

White blood cells (that recognize pathogens and trigger the immune response) are, what?

Answer 46

Killed off, allowing for multiple other infections to develop