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