Exam 1 (according to study guide) Flashcards
- MICRO
M: microscopic I: independent units C: comparatively less complex R: Rapid rate of reproduction O: Omnipresent
Areas of human body where microbes are present
skin, intestine are the 2 largest microbe areas
oral cavity, nasal cavity, external areas of urogenital system
Areas of body that are sterilized (no microbes)
Blood, brain, bone, bladder
- mutualistic relationship between human and microbes
For them:
- attachment site
- moisture/appropriate temp
- nutrient availability
- ready access for O2
For us:
- critical Vitamin (such as vit K for blood coagulation)
- eliminate toxin to aid digestion
- inhibit other colonization of pathogen (competition for nutrient, space, etc)
- ward of deadly germ (our normal flora of urogenital system help maintain urine acidic PH to make habit inhabitable for some)
- guide our immune system (condition it)
Which Bacteria produces an essential vitamin for us?
what causes VItamin K deficiency?
E.Coli (bacteria) produces vitamin K ( needed for blood coagulation)
E.Coli is found in intestine.
Newborn are given Vitamin K shot @ heel.
Adults usually have sufficient Vitamin K EXCEPT:
VIT K deficiency:
1) large intestine surgical removal
2) long term antibiotic
3) defect in bile synthesis (vitamin K is fat soluble)
Microbiome vs Microflora
Microbiome is the total genome composition of all the microbes present internally as well
as on skin surface.
Microbiome is NOT synonymous with microflora.
microflora is old term used to differentiate when referring to different colonies of microbes.
Transient vs Permanent Microflora
Permanent vs temporary
temporary bc:
1) competition from other microbe for nutrient, space, etc
2) elimination by body defense cells
3) physical/chemical changes in body that dislodge them (bacteria on skin and we sweat for example, the salt kills them)
Binomial nomenclature for microbes
1 name is GENUS
2 name is species name
ex) E-Coli
E) is from theorsore esherich
coli is species, from colon.
thus E(where it came from) and Coli(the species)
3 domain of organism group
living and nonliving (virus, viroids, prions)
within living is 3 domain
1) archea (prokaryote)
2) bacteria (prokaryote)
3) eukarya (eukaryote) (which is subdivided further into algae, protozoa (both protist), fungi, and helminths
what are the two protist?
and what is protist?
algae and protozoa
protist: Any of numerous eukaryotic organisms that are not fungi, plants, or animals and are chiefly unicellular or colonial. Protists that are multicellular do not have cells differentiated into tissues. The protists include the protozoans, certain algae, oomycetes, and slime molds
Chitin =?
Cell wall of Fungi (target of anti fungals)
cellulose= ?
cell wall of the Algae
peptidoglycan=?
cell wall of bacteria
psedopeptidoglycan =?
cell wall of archea
Recall 4-5 differences between prokaryotes and eukaryotes
Prokaryote has nucleoid area, Eukaryote has nucleus
pro has one circular chromosome, euk has multiple chromosome
pro has only non membranous organelle (ribosome and cytoskeleton). very primitive. Euk has both membranous and non membranous organelle (mitochondria, golgi app., etc)
pro has cell wall (peptidoglycan), euk only have simple one (if it even has one)
pro only has NON histone protein, Euk has both histone and non histone protein (associated with DNA)
pro divide via binary fission, EUK divide via mitosis.
List / identify 2 non membranous organelles of prokaryotes
ribosome and cytoskeleton
advantage of lacking membranous organelles in bacteria
less energy usage during cell division
Do prokaryotes have histone proteins like eukaryotes ?
No, prokaryote only has NON histone protein whereas eukaryote has both histone and non histone protein (which are associated with DNA)
Binary fission in bacterial cell ( no questions with details). Do spindle fibers participate in
this type of division ?
No.
bacteria is a prokaryote thus it divides via binary fission and do not have the participation of spindle fiber (which is part of mitosis)
What are infectious agents? List the 3 infectious agents. Provide at least 2 features of each
member of the infectious agents
1) Viruses
2) viroids
3) prions
Viruses: protein coat (capsid), only has either DNA OR RNA gnome, depend on host cell, passive movement, form via de nova assembly (no binary fission or mitosis, it freshly produced), grouped in families, grey area between considered living vs non living (bc once its in a host, it acts like a living cell but when outside can be crystallized and act non living and passive.
Viroids: affect plants. no known pathogen.
Prions: no genetic material.
altered from normal c-prp to p-prp via assembly.
can be inherited and/or transmitted.
What are obligate
intracellular parasites ?
members of Infectious agents group invades host cells and
directs the biochemical machinery and cellular resources for their own replication.
Additionally, they use and abuse cellular resources and host cell is taken as hostage
How are viruses transmitted between hosts -
actively / passively
passively, they lack flagella or anything for motility thus are transmitted passively (environment, aerospace)
Do viruses have
cytoplasm and organelles ?
No
Are Virus able to survive outside the biochemical environment
of a host cell ?
No
Why viruses are called as particles and not cells ?
because they are not living organism (have no organelles, do not reproduce (without a host))
DNA AND RNA VIRUS
remember, virus can only have either dna or rna. never both
DNA VIRUS:
Herpes simplex virus, HPV, small pox a
RNA:
Polio, common cold, rabies, influenza and HIV viruses SARS, COVID 1, 2
Why viruses are NOT referred to as inert particles (they are however called particles but not INSERT)? How would you defend this
statement
once inside host cells, virus behaves as any living organism and plays an
active role in delivery of nucleic acid to appropriate site for replication, diverting cellular
resources as well as initiating replication cycle; so viruses are positioned in the grey area
between living organisms and nonliving objects
Why viruses don’t fit into the classical definition of cell
b/c there is no organele, no glucose metabolism, no chemical rxn to make ATP, unlike bacteria which can.
virus dont metabolize, respire, or grow; they lack basic enzyme for many simple metabolic processes that characterize life @ cellular level
thus virus is more “grey” because it does act like a living organism ONCE INSIDE A HOST
Are virus crystallizable like
urea, uric acid etc
YES
Do viruses have motility appendages like cilia and flagella ? Do they make spores like some
bacteria ?
NO
How viruses replicate and make more copies of themselves ?
formed via de novo assembly (freshly produced) @ host cell. they do not do binary fission or mitosis/divide.
no spores like some bacteria.
Zoonotic virus
these can be life threatening:
Ebola (in bat)
West Nile
rabies
novel Coronavirus
( which originated from animals and jumped to humans)
Be able to identify 2 common features of all viruses
1) they all have a capsid that encloses the nucleic acid gnome
2) they enter and exit host cell following replication
Trivial viral diseases of humans
cold sores of Herpes simplex
and common cold
cytomegalovirus (viral disease)
Asymptomatic infection
shedded in all body fluids
and no harm in immunocompetent individuals.
Norovirus infection (virus)
stomach flu.
targets the intestinal epithelial cells and those are
replenished very quickly ( high turnover rate) ; so affected individuals recovers fast
Mumps (virus disease)
causing infection in more than 1 organ system – salivary / parotid glands as
well as the testis in males and can cause sterility.
prions
proteinaceous, infectious, virion
no genetic material
normal is c-prp (alpha helix)
bad misfolded is p-prp (beta helix)
converted via “templating”
normally similar to brain protein (neuronal membrane protein)
slow incubation period (over 20 years)
insensitive to protease, uv ray, high temp. etc)\
is both inheritable and/or transmisable, dual behavior unknown amongst other micro pathogen
Why prions infection is not a common disease despite the fact we have the specific
protein as a membrane protein
because adjacent protein and polysaccharides in membrane lipid rafts forces the PRPc into correct shape (remain in alpha helix shape)
HOWEVER
more prone to prion disease if:
c-prp has methionin amino acid @ 129 position, then higher risk.
Differences between transmission of sporadic, inheritable and infectious prions.
inherit: mutation in prpc gene initiate templating
sporadic: random, gene is normal but altered
infectious:
- due to ingestion(contaminated meat, etc)
- transplantation of infected tissue
- contaminated surgical instrument
- use of hormones
Explain 4-5 ways infectious prions could be possibly transmitted
- due to ingestion(contaminated meat, etc)
- transplantation of infected tissue
- contaminated surgical instrument
- use of hormones
Identify some human and animal disease associated with prions
Human;
kuru
CJD (from inability to sterilize by standard method), vCJD (from eating infected food),
animal:
scrapie (sheep, goat) scratch to death
wasting disease (elk)
mad cow disease (ovine spongiform encephalpathy)
cure: kill entire herd, incinerate w extremely high temperature. strictly regulated protocol.
Some treatment options for prion disease in humans.
Do antihistamine, antimalarial and
anti psychotic drugs have shown to alleviate symptoms of prion related diseases in animals ?
Yes
Why are bacteria grouped as dynamic organisms? Recall 3 advantages associated with
structural simplicity of bacterial cells.
well adapted for survival and to new environment
bacteria structure simplicity helps in
reducing cell energy during cell division
rapid rate of reproduction which helps in:
evolution, genetic change, broader distribution
How Archae differs from bacteria group?
archea has a psudopeptidoglycan cell wall (as oppose to bacteria peptidoglycan cell wall)
archea is nonpathogenic
inhibit extreme temperature (unlike bacteria)
Recall 3 divisions of Archae and some of their
features as discussed in class.
1) halophiles: halobacterium (extreme salty environment)
2) thermophiles (extreme high temperature environment)
3) Methanogens ( found in cow intestine) produces byproduct of metabolism of methane instead of CO2.
Identify the major differences between bacteria and viruses
bacteria is independent, virus is not
bacteria has a cell wall, virus has a capsid
bacteria has organelle (cytoplasm, ribosome, membrane) virus do not
bacteria has dna/rna. virus only has one of them, either or.
What are Protists? How members acquire nutrient materials ?
protist: algae, protozoa
protist: Any of numerous eukaryotic organisms that are not fungi, plants, or animals and are chiefly unicellular or colonial.
Algae acquire nutrient via photosynthesis
protozoa ingest particle of organic matter
clinically important Protozoa
Trichomonas vaginalis\
common STD, affect both M/F.
Trichomoniasis is an infectious disease caused by the parasite Trichomonas vaginalis. About 70% of women and men do not have symptoms when infected. When symptoms do occur they typically begin 5 to 28 days after exposure. Symptoms can include itching in the genital area, a bad smelling thin vaginal discharge, burning with urination, and pain with sex. Having trichomoniasis increases the risk of getting HIV/AIDS. It may also cause complications during pregnancy
Identify the natural decomposers of microbial world. Provide 1-2 unique features of this
group. How do they differ from bacteria ? Identify one resemblance with bacteria. Are
they motile like some bacteria ?
Fungi.
they have cell wall: chitin
uni/multicellular
different from bacteria: unlike bacteria, they are eukaryote.
similar to bacteria: they absorb nutrient
motile like bacteria? NO
Features of helminthes; how are they different from others ? Do they have invertebrates
and vertebrates host in their life cycle ? or both.
3 class: round worm, tape worm, flukes.
both as host.
complex life cycle, multiple host, cause disease in human and animal. asexual.
What is pleomorphism ?
name 2 example
variation in shape and size
EX: corynebacterium mycoplasma pneumonia (walking pnemonia)
Morphology and arrangement of prokaryotic cells (shapes and groupings) as discussed in
class
3 main:
cocci: round, sphere
bacilli: rod shaped
spirals: rigid is spirillum, flexible is spirochete.
others:
vibrios (slightly curved rods)
coccobacillus: hybrid of cocci and baccilli, in between (rod sphere)
star/square shaped
Identify / recall the 2 factors in the bacterial cell’s arrangement
1) plane of division
2) daughter cell remain attached or separated
arrangement for cocci cells
1) diplococci (2 sphere)
(neisseria gonorrhea)
2) streptococci (chain)
(streptococcus pyogenes (strep throat) and streptococcuc pnemonia
3) staphylococci: random plane, cluster. of grape
staphyloccus epidermis (remain on skin) staphyloccus aureas (cause wound infection) (Gram positive)
4) sarcinae (3 plane) cuboidal
no pathogen
5) tetrad: 2 plane, perpendicular (4 sphere)
micrococcus luteus
arrangement for bacilli
less variation bc only divide along shorter axis
strepto bacilli- chain
diplobacilli-2
v shape: V
palisade: fence like, stacked.
Are spiral bacteria grouped?
No
shape of neisseria gonorrhea
diplococci
medically important spirochete (flexible spiral bacteria)
Borrelia sps (lyme disease) Leptospira sps (leptospirosis) Treponema sps(syphilis bacteria )
Borrelia sps (lyme disease) Leptospira sps (leptospirosis) Treponema sps(syphilis bacteria )
SHAPE
SPIRAL bacteria
spirochete (flexible)
Leptospira sps (leptospirosis)
Leptospira enters body by break in skin and spreads via blood but
is rarely fatal – cause of leptospirosis
blood infection
Bordetella sps uniquenesss in shape
bordetella pertusis=? (what disease)
coccobacillus (hybrid between cocci and bacili)
bordetella pertusis: whooping cough pathogen
Vibrio cholerae and E.coli difference in shape
E coli is a bacilli (rod)
vibrio cholerae is a vibrios (slightly curve rods)
Uniqueness of Vibrio vulnificus
(emerging pathogen which is genetically similar to V cholerae).
both Vibrio vulnificus and vibrio cholerae are vibrios(slightly curve rods) however, vibrio vulnificus can be fatal.
V vulnificus is found in warm salty water around globe and is able to infect by
penetration directly into a deep wound / cut or scratch
Mycoplasma (walking pnemonia)
and Corynebactyerium sps
Uniqueness of
Mycoplasma sp.
PLEOMORPHIC (variation in shape and size)
Mycoplasma penumonia is non fatal (walking pnuemonia)
also, it is one of the smallest living organism,
arrangement:
1)Neisseria gonorrhoeae
2) Streptococcus pneumoniae
3) Streptococcus pyogenes
4) Micrococcus sps
1) Neisseria gonorrhoeae: diplococci
2) streptococci
3) streptococci
4) tetrad (4) 2 plane
Staphylococcus aureus
opportunist pathogen
causes wound infection
usual member of the microbiota of the body
While these germs don’t always cause harm, they can make you sick under the right circumstances
Staphylococcus aureus is a Gram-positive, round-shaped bacterium, a member of the Firmicutes, and is a usual member of the microbiota of the body, frequently found in the upper respiratory tract and on the skin. It is often positive for catalase and nitrate reduction and is a facultative anaerobe that can grow without the need for oxygen.[1] Although S. aureus usually acts as a commensal of the human microbiota it can also become an opportunistic pathogen, being a common cause of skin infections including abscesses, respiratory infections such as sinusitis, and food poisoning.
Corynebacterium sps
can be V shaped, palisade, or pleomorphic!
Bacteria structure:
layers:
innermost
mid
outermost
long tail
short “tail”
pouch that contain pigment (like similar to chloroplast)
inner: plasma membrane
mid: cell wall (peptidoglycan)
outermost: capsule
long tail: flagella
short: fimbraie/pili
pouch: chromatophore
