Chapter 4-6 Flashcards
What are the 4 things ALL bacteria have
Phospholipid cell membrane
Chromosomal DNA
Ribosomes/protein production
Cytoplasm
What do flagellum enable
locomotion
Define fimbriae
fine hairlike birstles extending from the cell surface that help in adhesion to other cells adn surfaces
Define pilus
an appendage used for drawing another bacterium close in order to transfer DNA to it
Define plasmid
small double stranded DNA molecule containing extra genes
Define pili
rigid tubular structure made of pilin protein
What is the function of pili
join bacterial cells for partial dna transfer called conjugation
Where are pili only found in
gram negative cells
Based on ____ information, the phylogenetic history can be deduced and we can infer the relationship of thousands of different bacterial species
genetic
What is an extremely useful and common way to classift bacteria?
by their cell envelope
What is the composition of cell envelopes
glycocalyx
cell membrane
cell wall
What are cell walls composed of
peptidoglycan
The cell wall is _____-like and composed of what 2 things (but the majority of it is ___________)
mesh-like; polysaccharide and peptide linker; peptidoglycan
In gram positive the peptidoglycan is ___________-
very thick
In gram negative the peptidoglycan is
very thin
What gram bacteria has 2 membranes
gram negative
Hans gram developed what method for distinguishing between two major classes of bacteria
gram staining
What are the 3 layers of gram negative bacteria
an outer membrane, thin peptidoglycan, and cell membrane
What staining color is gram positive and why
thick peptidoglycan of the gram positive cell traps the crystal violet mordant complex and makes in inaccessible to the decolorizer leaving the cell purple
What staining color is gram negative and why
the cell walls are thinner and the crystal violet is easy to remove with the decolorizer so the cell stains red
In gram negative the alcohol does what to the outer membrane
dissolves it which increases the loss of dye
Which gram bacteria is overall more thick
gram positive
Does gram positive have an outer membrane
no
Does gram negative have an outer membrane
yes
Which gram bacteria is more penetrable
gram positive
Why doesn’t penicillin target human cells
we lack peptidoglycan
coccus
spherical ball shaped bacteria
bacillus/rod
cylindrical (longer than wide)
Vibrio
comma shaped
Spirillum
spiral shaped cylinder/corkscrew
Spirochete
more flexible form that resembles a spring
Spirilla and spirochetes have gram reaction (cell wall type) to
gram negative bacteria
Plasmid DNA is
circular
What can confound the classification of bacterial species?
extrachromosomal DNA
Define species
collection of organisms that show similar patterns of traits
define subspecies or strain
sub group that share one unique structure or gene
What is the most ancient of all life forms
archaea
Archaea are extremophiles meaning
that they can evolve in extreme conditions
What are archaea more closely related to
eukaryotes than bacteria
Why are archaea more related to eukaryotes
cell wall is more similar to eukaryotic (no peptidoglycan)
share a number of ribosomal rna sequences not found in bacteria
protein synthesis and ribosomal subunit sturctures are more similar
What theory is associated with the history of eukaryotes
the endosymbiotic theory
What does the endosymbiotic theory say
the nucleus containing cells of animals, plants, and fungi arose during evolution through the merging of cells of two types of microorganisms–archaea and bacteria
Function of cytoskeleton
structure support
Function of ribosomes
protein production
Function of cytoplasm
water based gel like solvent
Function of nucleus
house genetic info
function of ER
protein production and secretion
Function of mitochondria
energy
Function of lysosomes
storage of material
An example of lysosomes
vacuolue
Function of golgi body
packaging and secretion of proteins
Function of phospholipid bilayer cell membrane
selective permeability
Function of glycocalyx
adherence to surfaces; development of biofilms and mats; protection
Cilia are similar to flagella but they are
shorter and more numerous only in certain protozoa and animal cells
Where is the ER
near the outer membrane of the nuclear envelope
Where is the golgi complex located near
the ER but not connected to
Order the following choices to reflect the evolution of the origin of euk cells:
- once engulfed the smaller cell provides some benefit within and to the larger for e.g. energy production
- over time, the symbiotic relationship becomes permanent and the two cannot exist independently
- a larger prokaryotic (possibly archeon) cell engulfs a smaller prokaryotic cell
- Once merged the two cells begin to co evolve additional internal structures also evolve into organelles, such as ER
3
1
4
2
What is one of the major differences between pro and euk cells
the size differential
What bacteria lacks chloroplast
cyanobacteria
What are a few structures that only some eukaryotes have
cell wall
flagellum
chloroplasts
Linear dsDNA is so ________ it can be split into chromosomes
large
What are the similarities with genome arrangement of pro and eukaryotes
dsDNA, genes in the genome
What are differences with genome arrangement between pro and eukaryotes
pro have circular, smaller genomes
euk have nucleus and require histones to compact their genome
__________ has highly complex structure with several levels of organization
chromatin
What encodes genes
nucleotide sequence
What helps compact DNA
histone proteins
A –>
G –>
T
C
What also assisting compacting
nucleosomes
Chromatids are ____ _____
tight coils
chromatids go to
chromosomes
What do all ribosomes have
2 subunites large and small containing both rRNA and ribosomal proteins
What does the small subunit do
monitor the complementarity between tRNA anticodon and mRNA
What does the large subunit do
catalyzes peptide bond formation rRNA
Euk ribosomes
______ large subunit; ______ small subunit
60s; 40s
pro ribosomes
____ large subunit; _____ small subunit
50s; 30s
How many types of proteins in euk ribosomes
70-80
How many types of proteins in pro ribosomes
53
Structural difference between ribosomes make pro ribosomes a good ___ _______
antibiotic target
Cell walls are composed of
chitin
Protozoan have no _______ wall and are non-____________________ protists
cell; photosynthesizing
how many cells are protozoans
unicellular but can be very large with highly specialized organelles
What is the most abundant microbe on earth
viruses
about _________ viral particles could fit in average bacteria
2000
______ million polioviruses could fit in an average human cell
50
What factor do viruses outnumber bacteria by
factor of 10
Why is there no universal agreement on how and when viruses originated
no fossil records
How can we track viruses
track integration events of some viruses over time to get an idea of their evolutionary history
Viruses are likely very old and originated from ancient ______ cells that predated LUCA
RNA
What was Louis pasteur postulation about rabies informing us
that it’s caused by living thing smaller than bacteria that was unable to be isolated and cultivated in the lab
What did ivanovski and beijerinch discover about viruses
infectious agent of tobacco plant–tobacco mosaic virus
Virus organization is ____ and ______ –only those parts needed to invade and use the host replicate itself
simple; compact
Viruses lack _____________ machinery
biosynthetic
What do viral genomes carry
minimum information and gened needed to invade host cell and redirect cell’s activity to make new viruses
Viral genomes have RNA _____ DNA but
or but never both
What is the RNA strand in virus
What is the DNA strand in virus
single stranded ss or double stranded ds
What has the smallest genome
viruses
What are viruses generally grouped by
grouped based on structure, chemical comp, and similarities to genetic makeup to indicate evolutionary relatedness
Why can some viruses enter only some types of human cells but not others
receptors protein embedded in host cell membrane
Define what animal virus multiplication does and what it has
evade host defenses; speedy replication and release
Some viruses _______ their DNA into the host
integrate
Define latent phase/disease and what happens
usually no or little symptoms of a disease but person is still infected with virus
Why can simple virus structure be difficult to drug development
hard to hit a chemical bulls-eye
What does hide in host cell mean
drug needs to also target host
What does population size increases fast mean in terms of drug development is challenging
easy for just one to evade host (immune system and/or treatment)
What part of the virus stimulates immune response of the host to produce antibodies that can neutralize the virus and protect the host cells against future infections
capsid and/or envelop
Define vaccines
artificial immunity, trains our immune system to recognize virus and prevent future infection
What do mRNA vaccines do
make proteins in order to trigger an immune response
What type of vaccine is MMR combined vaccine
has live-attenuated vaccine
What do inactivated vaccines do
inactive vaccines use the killed version of the germ to cause a disease
How do prokaryotes reproduce
binary fission
how do euk reproduce
mitosis
how do viruses reproduce
need host
