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Flashcards in microbiology Deck (43):
1

viruses are

obligate intracellular parasites. relies on host machinery whenever possible

2

viral structure and function

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

3

what is the difference between viruses infecting animals vs bacteria

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

4

lytic cycle of phages

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

5

lysogenic cycle of phage

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

6

transduction

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

7

lysogenic cycle all becomes known as

a provirus

8

retroviruses need

RNA dependent DNA pol

9

subviral particles include

viroids and prions

10

prions

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

11

viroids

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

12

3 domains include

bacteria & archae= include prokaryotes
eurkarya=include eukaryotes

13

eukaryotic domain

animalia, plantae, fungi

14

plasmid

this is a circular piece of double-stranded DNA

15

lysozymes to bacteria

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

16

gram negative

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

17

endotoxins

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

18

exotoxins

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

19

monotrichous

are flagella at only one end

20

amphitrichous

flagella at both ends

21

pentrichous

multiple flagella

22

eukaryotic flagellum

9+2 arrangement of microtubules

23

pili

long projections on bacterial surfaces involved in attaching to different surfaces

24

autotrophs

utilizes co2 as their carbon source

25

heterotrophs

rely on organic nutrients

26

chemotrophs

get their energy from chemicals

27

phototrophs

get their energy from light

28

chemoautotrophs

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

29

chemoheterotrophs

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

30

photoautotrophs

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

31

photoheterotrophs

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

32

doubling time

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

33

faculative anaerobes

will use oxygen when it is around

34

tolerant anaerobes

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

35

obligate anaerobes

are poisoned by o2

36

stationary phase

when toxins begin to accumulate

37

in unfavorable conditions some bacteria create

endospores

38

transduction

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

39

transformation

if pure DNA is added

40

conjugation

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

41

Hfr

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

42

domain archae how do they differ from other bacteria

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

43

cyanobacteria

are responsible for nitrogen fixing in marine environments