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what are 4 basic microbes that can cause pathogens?
what kingdom are they each/
- bacteria: prokaryote
- viruses: non living
- fungi: eukaryote
- protoza: eukaryote
differences between bacteria and eu cells?
- nucleus: eukaryotes - membrane-bounded, bacteria: floating (also plasmids)
- RB: eukaryotes: 80S (60S & 40S), bacteria: 70S (50S & 30S)
- organelles: eukaryotes - mitochondria, golgi apparatus, lysosomes, peroxisomes and ER, bacteria: not those
bacteria divide by binary fission
what are the unifying princples of a) viral structures b) viral replication?
a) viral structures: all viruses package their genomes inside a particles that mediates transmission of the viral genome from host to host
b) viral replication: the viral genome contains the info for initiating and completing an infectious cycle within a susceptible, permissve cell.
what are capsids?
what is nucleocapsid?
The capsid surrounds the virus and is composed of a finite number of protein subunits known as capsomeres, which usually associate with, or are found close to, the virion nucleic acid.
nucleocapsid: capsid protein + viral nucleic acid
what is the baltimore classification system?
dsDNA viruses
ssDNA viruses
dsRNA viruses
(+)ssRNA viruses
(-)ssRNA viruses
ssRNA-RT viruses
dsDNA-RT viruses
what type of virus (from baltimore classification) is:
- coronavirus
- influenza
- HIV?
- coronavirus: (+)ssRNA viruses
- influenza:(-)ssRNA viruses
- HIV: ssRNA-RT viruses
Role of:
Reverse transcriptase ?
Integrase ?
Protease ?
RNA polymerase ?
Reverse transcriptase – turns +ssRNA into DNA
Integrase – integrates viral DNA with host genome
Protease – help create viral building blocks
RNA polymerase – forms mRNA before going to ribosome
basal cells of epidermis cells are attached to what?
what do adherens and desmosomes, tight junctions and gap junctions do in epidermis basal lamina?
basal cells of epidermis cells are attached to what?
what do adherens and desmosomes, tight junctions and gap junctions do in epidermis basal lamina?
how do you differentiate betweeen melanocytes and keratinocytes?
- *melanocytes**: smaller nucleus, cytoplasm looks like halo
- *keratinocytes**: brown looking
what do merkel cells do ? found? appearance?
- *merkel cells:**
- location: **stratum basale
- appearance:lobed nucleusanddenser cytoplasm.** looks like a bean. (hard to differentiate with melanocytes)
- function: underlying sensory nerve endings - light touch sensory. aso possess antigenic markers
what do merkel cells do ? found? appearance?
- *merkel cells:**
- location: **stratum basale
- appearance:lobed nucleusanddenser cytoplasm.** looks like a bean. (hard to differentiate with melanocytes)
- function: underlying sensory nerve endings - light touch sensory. aso possess antigenic markers
explain the major ways microbe adherence can occur [3]
adhesive hair-like structures
- *1. pili or fimbriae**: adhesive hair-like structures formed of proteins
subunits: major subunit - pili. minor subunit - tip - *2. afimbrial adhesin:**
- membrane or membrane anchored protein, interacting directly with host cell receptors.
- indirect interaction with hosts cell receptors via bridging molecules (e.g. fibronectin binding proteins)
- *3. biofilms:** adhesion to solid surfaces and infections
- community of bacteria that produce sugar polymer, known as extrapolymeric substance (EPS), allows biofilm to attach to a surface
what are the different stages of disease caused by a microbe?
- *1. incubation period**
- asymptomatic period
- *2. prodromal stage**
- vauge feelings of non-specific complaints
- *3. period of illness (invasion)**
- sympotmatic and more specific signs
- effects of toxins
- *4. convalescences**
- persons of immune system responds to infection (or medical intervention)
label these pls xoxo
why are biofilm associated infections really problematic? (2)
extreme resistance to antiobiotics and other anti-microbrial agents
- high resistance to host immune defences