Microbiology

Question 1

Virus facts!

Answer 1

1. ) viruses can only reproduce with cells.
2. ) they can’t do any rxns on their own, but they may have stored some ATP
3. ) virus’s are not cells or living organisms.

Question 2

How Bacteriophage do get into plant and in human cells?

Answer 2

They get in via puncturing for plant and they get internalized by animal cells

Question 3

What purpose does overlapping serve for viruses?

Answer 3

It allows the virus to make more than one protein within a given stream of the genome

Question 4

The envelope of animal viruses is composed of what?

Answer 4

Phospholipids, proteins, carbs from original host membrane.

Question 5

When are viruses naked? Animal, plant, or bacteria?

Answer 5

Plant and bacteria due to the cell wall

Question 6

Bacteriophage life cycle?

Answer 6

1. ) gene binds to bacterial cell wall via adsorption
2. ) via eclipsing or penetrating the viral genome gets inserted
3. ) either lytic cycle or lysogenic

Question 7

Explain the lytic cycle of phages?

Answer 7

1. ) host’s genome gets broken down via hydrolases.
2. ) mult copies of the phage genome gets copied via host dNTP.
3. ) capsid gets formed
4. ) lysozyme is produced and it breaks down cell walls

Question 8

What is the lytic cycle good for?

Answer 8

Great to increase number if viruses, but it kills the host

Question 9

What is co-infection?

Answer 9

When two viruses infect the same cell

Question 10

Lysogenic cycle?

Answer 10

Phage genome gets incorporated into host genome making a prophage. Host is now a lysogen.
Propage gets replicated until activated to go through excision and go to lytic cycle

Question 11

Animal cells and provirus

Answer 11

Much like the lysogen if model of bacterial viruses. It lies dormant for a while and then expresses itself when the host is user stress

Question 12

+RNA virus is what

Answer 12

Single stranded viral RNA which serves as an mRNA.

It is RNA dependent RNA polymerase. So it encodes the RNA pol and it doesn’t need to carry.

Question 13

-RNA virus

Answer 13

Must carry RNA dependent RNA pol and it needs to carry it too.

Question 14

Retrovirus

Answer 14

Encode reverse transcriptase and at times can be dormant proviruses.

Question 15

Bacterial structure

Answer 15

No membrane bound organelles. So like ribosomes are found in eu and pro since they are not membrane bound

Question 16

Conjugation

Answer 16

Bacterial exchange of information

Question 17

Cell membrane and cell wall

Answer 17

The cell membrane is a lipid bolster which is surrounded by a peptidoglycan complex polymer which is unique to prokaryotes. Bacterial AA are D

Question 18

What would happens to a cell wall when it comes in contact with a lysozyme?

Answer 18

It degrades and the fragile left over of a cell membrane is a protoplasm

Question 19

Gram positive

Answer 19

Dark purple stain. They have a thick peptidoglycan layer with nothing beyond that

Question 20

Gram negative

Answer 20

Thin peptidoglycan later followed by peri plastic space which may degrade abx. Then another peptidoglycan layer.

Question 21

Endotoxins

Answer 21

Only within gram neg bacteria also generally harmless, but because our body tries over fighting it we go into septic shock from all the chemicals

Question 22

Exotoxins

Answer 22

Very poisonous and carried by both pos and neg bacteria and they compete with our own bacteria

Question 23

Capsule of bacteria

Answer 23

Made up of poly sacch goo that makes it all sticky.

Question 24

Flagella

1. ) monotrichous
2. ) amphitrichous
3. ) peritrichous

Answer 24

1. ) one flagella
2. ) flagella on both sides
3. ) multiple flagella

Question 25

Facultative anaerobes

Answer 25

Use oxygen when it is around, but don't need it

Question 26

Tolerant anaerobes

Answer 26

Grow in the presence and absence of oxygen. Essentially don't use it within their metabolism

Question 27

Obligate anaerobes

Answer 27

Poisoned by oxygen

Question 28

Within aneoribic respiration

Answer 28

Oxygen is not the final electron acceptor

Question 29

The coding sense strand has the same sequence as what?

Answer 29

The mRNA transcript

Question 30

What initiates prokaryotic transcription?

Answer 30

A halo enzyme

Question 31

What regulates prokaryotic transcription?

Answer 31

Repressive enzymes. They are always on and inductive are always off

Question 32

What is a lac operon?

Answer 32

Coding sequence for enzymes it's an upstream regulatory sequence for control sites

Question 33

Where does transcription take place in pro what about eu?

Answer 33

Cytoplasm for pro and it can occur at the same time as translation. Eu has transcription and editing occur in the nucleus where it gets transferred over the nuclear membrane and then gets translated in the cytoplasm. Can't occur at the same time.

Question 34

Chemoautorophs

Answer 34

Build organic molecules from co2

Question 35

Chemo heterotrophs

Answer 35

Humans are chemoheterotrophs. We need organic molecules like glucose made by other organisms

Question 36

Photo autotrophs.

Answer 36

Use co2 for carbon and get energy from the sun

Question 37

Photoheterotrophs

Answer 37

Require other molecules for carbon but use sun for energy

Question 38

Auxotroph

Answer 38

Can't survive in minimal media

Question 39

Binary fission

Answer 39

Essentially mitosis for bacteria. They replicate until there is enough material for two cells

Question 40

How many cells will grow of bacteria

Answer 40

2^n where n is number of divisions

Question 41

Endospore formation

Answer 41

Which are done by gram positive. It has a peptidoglycan shell, has genomes and ribosomes, and it can survive up to 100C works when conditions are perfect

Question 42

Metabolic reactivation

Answer 42

Occurs during stationary phase of life cycle it's important for sleeping through while having lack of nutrients.

Question 43

3 types of genetic exchange of bacteria is?

Answer 43

Transduction Transformation Conjugation

Question 44

Transduction

Answer 44

Genetic DNA is transferred

Question 45

Transformation

Answer 45

Uptake from surroundings

Question 46

Conjugation

Answer 46

Recombination can occur F- becomes F+. Te male has the high frequency recombination within its genome