microbiology

Question 1

viruses are

Answer 1

obligate intracellular parasites. relies on host machinery whenever possible

Question 2

viral structure and function

Answer 2

all viruses possess a nucleic acid genome packaged into a protein shell. DNA or RNA

Question 3

what is the difference between viruses infecting animals vs bacteria

Answer 3

in bacteria they have to inject because the bacteria has a cell wall

Question 4

lytic cycle of phages

Answer 4

first viral gene product made is hydrolase and that degrades the entire host genome
multiple copies of the phage are produced using the dNTPs from host genome
lysozyme is produced (late gene) it destroys the bacterial cell walls releasing all of the virus to do the next cycle

Question 5

lysogenic cycle of phage

Answer 5

upon infection the phage genome is incorporated into the bacterial genome and is referred to as a prophage host called lysogen

Question 6

transduction

Answer 6

when a virus infects new cells and carries with it some of the host genome

Question 7

lysogenic cycle all becomes known as

Answer 7

a provirus

Question 8

retroviruses need

Answer 8

RNA dependent DNA pol

Question 9

subviral particles include

Answer 9

viroids and prions

Question 10

prions

Answer 10

are infectious agents, do not follow central dogma they are self-replicating proteins. Is a misfolded version of a protein that already exists. when prions come in contact with the normal they change shape and become infectious

Question 11

viroids

Answer 11

consist of a short piece of circular single-stranded RNA with extensive self-complimentarity

Question 12

3 domains include

Answer 12

bacteria & archae= include prokaryotes

eurkarya=include eukaryotes

Question 13

eukaryotic domain

Answer 13

animalia, plantae, fungi

Question 14

plasmid

Answer 14

this is a circular piece of double-stranded DNA

Question 15

lysozymes to bacteria

Answer 15

destroy the peptidoglycan cell wall resulting in an osmotically fragile structure called protoplast

Question 16

gram negative

Answer 16

have a thinner layer of peptidoglycan in their cell wall but have an additional outer layer of lipopolysaccharides. Gram negative have stronger protection and are less likely to lyse

Question 17

endotoxins

Answer 17

are normal components of the outer membrane of gram negative bacteria that aren’t inherently poisonous. cause host trouble when the bacteria die as the outer membranes are disintegrated and the endotoxins are released

Question 18

exotoxins

Answer 18

are toxins released by bacteria to outcompete the bacteria that inhabit this area

Question 19

monotrichous

Answer 19

are flagella at only one end

Question 20

amphitrichous

Answer 20

flagella at both ends

Question 21

pentrichous

Answer 21

multiple flagella

Question 22

eukaryotic flagellum

Answer 22

9+2 arrangement of microtubules

Question 23

pili

Answer 23

long projections on bacterial surfaces involved in attaching to different surfaces

Question 24

autotrophs

Answer 24

utilizes co2 as their carbon source

Question 25

heterotrophs

Answer 25

rely on organic nutrients

Question 26

chemotrophs

Answer 26

get their energy from chemicals

Question 27

phototrophs

Answer 27

get their energy from light

Question 28

chemoautotrophs

Answer 28

build organic molecules from co2 using the energy of chemicals. They obtain energy by oxidizing inorganic molecules

Question 29

chemoheterotrophs

Answer 29

require organic molecules such as glucose as their carbon source for energy

Question 30

photoautotrophs

Answer 30

get energy from sun but require an organic molecule made by another organism as their carbon source

Question 31

photoheterotrophs

Answer 31

get energy from sun but require an organic molecule made by another organism as their carbon source

Question 32

doubling time

Answer 32

the time it takes for the population of bacteria to double its number

Question 33

faculative anaerobes

Answer 33

will use oxygen when it is around

Question 34

tolerant anaerobes

Answer 34

can grow in the presence of o2 but do not metabolize it

Question 35

obligate anaerobes

Answer 35

are poisoned by o2

Question 36

stationary phase

Answer 36

when toxins begin to accumulate

Question 37

in unfavorable conditions some bacteria create

Answer 37

endospores

Question 38

transduction

Answer 38

transfer of genomic DNA from one bacterium to another by a lysogenic phase

Question 39

transformation

Answer 39

if pure DNA is added

Question 40

conjugation

Answer 40

bacteria reproduce asexually. bacteria that have the f factor are F+ male and bacteria that do not are F- factor

Question 41

Hfr

Answer 41

a cell with f factor integrates into its genome is Hfr (high frequency recombination cell)

Question 42

domain archae how do they differ from other bacteria

Answer 42

their cells lack peptidoglycan. have introns and use of many mRNA sequences

Question 43

cyanobacteria

Answer 43

are responsible for nitrogen fixing in marine environments