Exam 2 Flashcards
what is the study of fungi called
mycology
is the number of serious of fungal infections increasing or decreasing
increasing
what are fungi
are they aerobic/anaerobic
aerobic or facultatively anaerobic chemoheterotrophs
what are the main job of fungi in the environment?
can they be parasites?
most fungi are decomposers, and a few are parasites of plants and animals
what does the fungal thallus consists of and what are they called?
fungal thallus consists of filaments of cells called hyphae
what is a mass of hyphae called
mycelium
are yeast aceullular or unicellular
unicellular organisms
how do fission yeast reproduce
divide symmetrically
how do budding yeast reproduce
asymmetrically
what are fungi buds that do not separate from the parent cell called
form pseudohyphae
what is dimorphic fungi at 37 degree Celsius
are yeastlike
what is dimorphic fungi at 25 degrees celcius
mold like
how are fungi classified
according to rRNA
how are sexual spores usually produced
in response to speical circumstances often changes in the enviroment
where can fungi grow
grow in acidic, low moisture, aerobic environments
what can fungi metabolize
complex carbohydrates
where do systematic mycoses affect the body
systemic mycoses are fungal infections deep within the body that affect many tissues and organs
where do subcutaneous mycoses affect the body
sub q mycoses are fungal infections beneath the skin
where do cutaneous mycoses affect the body
cutaneous mycoses affect keratin-containing tissues such as hair, nails and skin
where do superficial mycoses affect the body
superficial mycoses are localized on hair shafts and superficial skin cells
what causes opportunistic mycoses
opportunistic mycoses are caused by fungi that are not usually pathogenic
what do opportunistic mycoses infect
opportunistic mycoses can infect any tissues however they are usually systemic
how can be fungi used in ecosystem
fungi are used for the biological control of pests
what is more common?
bacterial spoilage of fruits grains and vegetables or mold spoilage
mold spoilage is more common
many fungi cause diseases in ___________
plants
what is a mutualistic combination of an alga (or a cyanobacterium) and a fungas
a lichen
when alga photosynthesized what do they provide for the lichen; the fungus provides a ________
providing carbohydrates
provides a holdfast
where do lichens colonize
lichens colonize habitats that are unsuitable for either the alga or the fungus alone
what may be classified on the basis of morphology as a crustose, foliose, or fruticose
lichens
what can be unicellular, filamentous or multicellular organisms
algae
most of what lives in aquatic environments
algae
are algae eukaryotic or prokaryotic
eukaryotic
are algae photoautotrophs or photoheterotrophs
photoautotrophs most are
what type of algae usually consists of a stipe, a holdfast, and blades
the thallus of multicellular algae
how do algae reproduce
sexually
what do photoautotrophic algae produce
oxygen
how are classified according to their structure and pigments
algae
where did red algae grow
grow deeper in the ocean than other algae
what type of algae have cellulose and chlorophyll a and b and store starch
green algae
what are the primary producers in aquatic food chains
algae are
yeast infection (candidiais) are most commonly found in:
newborns, people with AIDS, and people being treated with broad spectrum antibiotics
what are arthropods
what do they do
what are examples of arthropods
animals with jointed legs, transmit disease.
include ticks, insects and some members of the mosquito family
what are helminths
what are they
how do they get nutrients
what is the life cycle
multicellular animals
chemoheterotrophs
get nutrients from ingestion through the mouth and some absorption
life cycle includes: egg larvae adult
fungi, protozoa, and helminths
what do they cause
how are they diagnosed
cause disease in humans
diagnosed by microscopic examination
alga disease are not infectious they are ______
what are the symptoms result from
intoxications
symptoms result from ingestion of alga toxic substance
arthropods that transmit disease are called _________
examples:
vectors
ex: west nile encephalitis
what is the fossil remains of planktonic algae
petroleum
are protozoa acellular or unicellular
are they chemoheterotrophs or chemoautotrophs
unicellular organisms
eukaryotic chemoheterotrophs
where are protozoa found
soil and water and as normal microbiota in animals
what is the vegetative form of protozoa called
trophozoite
how do protozoa asexually produce
fission budding or schizogony
how do protozoa sexually reproduce
conjugation
explain ciliate conjugation by protozoa
two haploid nuclei fuse to produce a zygote
how do some protozoa protect themselves in adverse enviromental conditions
can produce a cyst that provides protection
what do protozoa cells walls have
protozoa have complex cells with a pellicle, a cytostome, and an anal pore
trichomonas and giardia lack ________ and have _______
lack mitochondria and have flagella
how do euglenozoan move and what do they lack.
what do they include
euglenozoan move by means of flagella and lack sexual reproduction
they include Trypanosoma
what has apical organells for penetrating host tissue
what do they include
Apicomplexa have apical organelles for penetrating host tissue;
include plasmodium and cryptosporidium
how do ciliates move
cilia
helminths
parasitic flatworms belong to which phylum
parasitic flatworms belong to the phylum Platyhelminthes
helminths
parasitic roundworms belong to which phylum
parasitic roundworms belong to the phylum nematoda
helminths are _______ animals and a few are parasitic of _______
multicellular animals
a few are parasites of humans
the adult stage of a parasitic helminth is found in the _________ host
the adult stage of parasitic helminth is found int eh definitive host
what do each larval stage of a parasitic helminth require
intermediate host
can helminths be monoecious or dioecious or both
helminths can be monoecious or diecious
flatworms are dorsoventrally __________ animals
what may parasitic flatworms lack
flatworms are dorsoventrally flattened animals; parasitic flatworms may lack a digestive system.
how do adult trematodes (or flukes) attach to host tissue
have an oral and ventral sucker
what is the name of the head and rest of body called on cestode (tapeworm)
scolex (head) and proglottids
how do eggs of trematodes turn into adults in the definitive host
eggs of trematodes hatch into free swimming miracidia that enter the first intermediate host; two generation of rediae develop; the rediae become cercariae that bore out the first intermediate host and penetrate the second intermediate host; cercariae encyst as metacercaria; the metacercaria develop into adults in the definitive host
true/ false
roundworms have a couple digestive system
true
what nematodes that can infect humans with their eggs
ascaris
Trichuris
Enterobius
what phylum do jointed legged animals including ticks and insects belong to
Arthropoda
what are arthropods that carry diseases called
vectors
how do vector borne diseases most effectively become eliminated
controlling or eradicating the vectors
what do viruses contain and what do they sometimes have
a single type of nucleic acid (DNA or RNA) and a protein coat, sometimes enclosed by an envelope composed of lipids, proteins, and carbohydrates
true/ false
viruses are obligatory intracellular parasites
true
how are viruses parasite
they multiply by using the host cells synthesizing machinery to cause the synthesis of specialized element that can transfer the viral nucleic acid to other cells
what is a host range
refers to the spectrum of host cells in which a virus can multiply
true/ false
most viruses infect only specific types of cells in one host species
true
how is a host range is determined by?
the specific attachment site on the host cells surface and the availability of host cellular factors
what is a virion
complete, fully developed viral particle composed of nucleic acid surrounded by a coat
what can viruses contain either or, never both and what do those contain (structure wise)
viruses contain either DNA or RNA never both, and the nucleic acids may be single or double stranded linear or circular or divides into several separate molecules
what is a capsid
the protein coat surrounding the nucleic acid of a virus
what is the capsid composed of
the capsid is composed of subunits capsomers which can be a single type of protein or several types
what is the capsid of some viruses enclosed by
an envelope consisting of lipids, proteins, and carbohydrates
what are some envelopes covered with
carbohydrates-protein complexes called spikes
what are helical viruses
resemble long rods, and their capsids are hollow cylinders surrounding the nucleic acid
what are polyhedral viruses
are many sided. usually the capsid is an icosahedron (a solid figure with twenty plane faces, especially equilateral triangular ones.)
what are enveloped viruses
covered by an envelope and are roughly spherical but highly pleomorphic. there are also enveloped helical virsues and enveloped polyhedral viruses
what is an example of a complex virus
complex viruses have complex structures. for example, many bacteriophages have a polyhedral capsid with a helical tail attached
how are viruses classified
classification of viruses is based on type of nucleic acid, strategy for replication and morphology
what do virus family names end with and what do genus names end with
virus family end in -viridae
genus names end in -virus
how do viruses grow
viruses must be grown in living cells
what are the easiest viruses to grow
to grow are bacteriophages
What dont viruses contain for energy production or protein synthesis
dont contain enzymes
In order for a virus to multiply what must the virus do
it must invade a host cell and direct the hosts metabolic machinery to produce viral enzymes and components
what do bacteriophages form on a lawn of bacteria
plaques
typical for more than one Viron is required to initiate what?
an infection in a cell (multiply of infection- MOI)
what does each plaque originate with
and the concentration of viruses is expressed how
originate with a single viral particle
the concentration of viruses is expressed as plaque forming units
where can some animal viruses be cultivated in
embryonated eggs
the plaque method mixes ___________ with host bacteria and nutrient agar
bacteriophages
where do cell cultures for animal or plant cells grow
culture media
what grows for a short time in vitro
primary cell lines and embryonic diploid cell lines grow for a short time in vitro(To make cultured, or in vitro, meat, scientists take the cells from an animal and then let them grow in a plant-based mixture of nutrients.)
where can continuous cell lines be maintained
vitro indefinitely
what can cause cytopathic in the cell culture
viral growth
(Cytopathic effect refers to structural changes in a host cell resulting from viral infection)
how are viruses identified
serological tests are used most often- detect antibodies in patient (4DX)
but may be identified by RFLP and PCR- nucleic acids
multiplication of bacteriophages
during which cycle a phage causes the lysis and death of a host cell
lytic cycle
multiplication of bacteriophage
during which cycle does prophage DNA incorporate in host DNA along with phage conversion and specialized/ generalized transduction
lysogenic cycle
true/ false
viruses contain very few genes needed for its replication
true
some larger viruses may contain 1 or more preformed enzymes
the lytic cycle
explain attachment
phage attaches by tail fibers to host cell
the lytic cycle
explain penetration
phage lysozyme opens cell wall
tail sheath contracts to force tail core and DNA into cell
the lytic cycle
explain biosynthesis
production of phage DNA and proteins
what is the lytic cycle of a T Even bacteriophage
attachment, penetration, biosynthesis
and maturation- assembly of phage particles
and release- phage lysozyme breaks cell wall
explain the lysogenic cycle
involves repressors (of phage origin) binding to an operator and blocking transcription of all other phage genes
explain generalized transduction
explain specialized transduction
explain the process of multiplication of animal viruses
attachment, penetration, uncoating, biosynthesis, maturation and release
attachment: viruses attach to cell membrane
penetration: by endocytosis or fusion
uncoating: by viral or host enzymes
biosynthesis: production of nucleic acid and proteins
maturation: nucleic acid and capsid proteins assemble
release: by budding (enveloped viruses) or rupture
explain the steps of multiplication of DNA virus
what is different about the sense strand (+ strand) RNA virus in regarding to multiplication
After uncoating, ssRNA viruses can synthesize proteins directly. Using the + strand as template, they transcribe – strands to produce additional + strands to serve as mRNA and be packaged into virus.
what is different about the antisense strand (- strand) RNA virus in regards to multiplying
After uncoating, ssRNA viruses with a – strand genome must transcribe a + strand to serve as mRNA before they begin protein synthesis. The mRNA transcribes additional -RNA
how do Double stranded RNA viruses multiply
dsRNA viruses, mRNA is produced inside the capsid and released into the cytoplasm of the host.
explain the multiplication of a retrovirus
summarize viral transcription and translation
what is a prion disease
transmissible spongiform encephalopathies (TSE) are a family of preogressive neurodegenerative disorders that affect both humans and animals
how are prion disease distinguished by
long incubation periods
characteristic spongiform changes associated with neuronal loss
failure to induce inflammatory response
define prion
abnormal, transmissible agent that is able to induce abnormal folding of normal cellular prion proteins in the brain, leading to brain damage and the characteristics signs and symtoms of the disease
what doesnt prion contain
does not contain RNA or DNA
why are prions hard to diagnoses
does not evoke any detectable immune response or inflammatory reaction is host animals
how do prions effect on a cellular level
mitochondrial stress and ER stress
is CWD endemic
yes
define pathology
study of disease
define etiology
the study of the cuase of the disease
what is pathogenesis
the manner in which a disease developments
define infection and disease
infection: colonization of the body by pathogens
disease: an abnormal state in which the body is not functioning normally
what is normal microbiota
permanently colonize the host (our own bacteria)
what is transient micrbiotia
may be present for days, weeks, or months (not normal (pathogenic))
what is symbiosis
relatioship between normal microbiota and the host
symbiosis
what is commensalism, mutualism, parasitism
commensalism- one organism benefits, and the other is unaffected
mutualism- both organisms benefit
parasitism- one organism benefits at the exepnse of the other
what are opporunitistic pathogens and how does this relate to our normal microbiota
normal flora but due to something can become pathogenic
what is microbial antagonism
competition between microbes, can be variable and host-dependent
how do normal microbiota protect the host
occupying niches that pathogen might occupy
producing acids
producing bacteriocins (proteins that inhibit the growth of bacteria of the same or closely related species)
what is Kochs Postulates
used to prove the cause of an infectious disease
established by Robert Koch in 1884
what are the actual steps to Kochs Postulates (4 steps)
1) the same pathogen must be present in every case of the disease
2) the pathogen must be isolated from the diseased host and grown in pure culture
3) the pathogen from the culture but cause the disease when it is inoculated into a healthy, susceptible lab animals
4) the pathogen must be isolated from the inoculated animals and must be shown to the original organism
what is a commubicable disease
a disease that is spread form one host to another (directly or indirectly)
what is a contagious disease
a disease that is easily spread from one host to antoher
what is a noncommunicable disease
a disease that is not transmitted from one host to another
occurrence of a disease
what is incidence
fraction of a population that contracts (new infections) a disease during a specific time
occurrence of a disease
what is prevalence
fraction of a population having a specific disease at a given time
occurrence of a disease
what is sporadic disease
disease that occurs occasionally in a population
occurrence of a disease
what is a endemic disease
disease constanlty present in the population
occurrence of a disease
what is a epidemic disease
disease acquired by many hosts in a given area in a short time
define acute disease
develops rapidly but lasts only a short time
define chronic disease
disease develops slowly; may have less sever reaction from host
define subacute disease
between acute and chronic
define latent disease
disease with a period of no symptoms when the causative agent is inactive
explain local infection
pathogens are limited to a small area of the body
explain systemic infection
an infection throughout the body spread throughout the body by blood
explain focal infection
systemic infection that began as a local infection
explain sepsis
toxic inflammatory condition arising from the spread of microbes, especially bacteria or their toxins, from a focus of infection
what is bacteremia
bacteria in the blood
what is septicemia
growth of bacteria in the blood
what is toxemia
toxins in the blood
what is viremia
viruses in the blood
what is a primary infection
acute infection that causes the initial illness
what is secondary infection
opportunistic infection after a primary (predisposing) infection
what is subclinical disease
no noticeable signs or symptoms (unapparent infection)
what is direct contact in regards to transmisison of disease
req close association between infected and suscpetible host
what is indirect contact in regards to transmission of disease
spread by fomites
what is droplet contact in regards to transmission of disease
transmission via airborne droplets
what is a mechanical transmission
arthropod carries pathogen on feet
what is a biological transmission
pathogen reproduces in vector
what is a vector
arthropods (fleas, ticks, and mosquitoes)
what is morbidity
incidence of a specific disease
what is mortality
deaths from diseases
what are 3 portals of entry for disease
mucous membranes
skin
parenteral route
what is parenteral route
access to the body through direct deposit to the inside
most pathogens prefer this portal of entry
what are the two steps of mechanisms to adhere
1) non specific adherence
2) specific adherence
what is nonspecific adherence
reversible attachment to of the bacterium to the eukaryotic surface
“docking”
what is specific adherence
irreversible permanent attachment of the microorganism to the survey “anchoring”
what do capsules do
prevent phagocytosis
cell wall components
what is M protein
resists phagocytosis
cell wall components
what is opa protein
inhibits T helper cells
cell wall components
what is mycolic acid
waxy lipid resists digestion
enzymes
what is coagulase
coagulates fibrinogen in blood (clotting)
enzymes
what is kinases
digest fibrin clots that are formed by body to isolate an infection
enzymes
what is hyaluronidase
hydrolyzes hyaluronic acid a type of polysaccharide that holds together certain cells of hte body, particularly in connective tissue (causes the blackening in some infections (is that necrosis???))
enzymes
what is collagenase
hydrolyzed collagen, making up connective tissue
enzymes
what is IgA protesases
destroy IgA antibodies that are particular important in the first immune response
what is antigenic variation
alteration of surface proteins in order to evade the immune response
how do bacteria penetrate into the host cell cytoskeleton
invasins
use actin to move from one cell to the next
what are the 4 basic mechanisms pathogens use to damage host cells
1-using the host nutrients
2-causing direct damage in immediate vicinity of the invasion
3-producing toxins, transported by blood and lymph, that damage sites before removed from original site of invasion
4- inducing hypersensitivity reactions
define: toxin, toxigenicity, toxemia, toxoid, antitoxin
toxin- poisonous substances that contribute (significantly) to pathogenicity
toxigenicity- ability to produce a toxin
toxemia- presence of toxin in the host blood
toxoid- inactivated toxin used in a vax
antitoxin- antibodies against a specific toxin
what is exotoxins
proteins produced inside pathogenic bacteria (part of growth and metabolism) then secreted into the surrounding medium during log phase
most common gram + but can be gram -
what are endotoxins
lipid portions of lipopolysaccharide’s (LPS) that are part of the outer membrane of the cell wall, they are liberated when the bacteria die and the cell wall breaks apart
GRAM - bacteria
lipid A is the endotoxin
what are the 3 pathogenic properties of helminths
1- use host tissue
2- presence of parasite interferes with host function
3- parasites metabolic waste can cause symptoms
define
susceptibility
immunity
susceptibility: lack of resistance to a disease
immunity: ability to ward off disease
what is innate immunity, what are the characteristics of it
defenses against any pathogen
present at birth
does not have a memory
always present and provide a rapid responses to protect us from disease
does not involve specific recognition o
how was innate immunity designed
to prevent microbes from gaining access into the body and eliminate those that do gain access
what is adaptive immunity
immune reaction, resistance to a specific pathogen once it has breached the innate immunity
explain the concept of immunity
host toll-like receptors (TLRs) that are non-specific and job is to recognize pathogen attach to pathogen-associated molecular patterns (PAMPs)
what do TLRs induce
cytokines that regulate the intensity and duration of immune response (cytokines are proteins)
what do cytokines recruit after induced by TLRs
recruit macrophages and dendritic cells, as well as other immune cells, to isolate and destroy the microbes as part of the inflammatory response
what are the 3 factors of the first line of defense
physical factors
chemical factors
normal microbiota and innate immunity
what are the 6 factors of the second line of defense
formed elements in blood
lymphatic system
phagocytes
inflammation
fever
antimicrobial substances
what does skin do as a physical factor
dermis and epidermis
dermis- inner thicker portion composed of connective tissue
epidermis- outer thicker portion in direct contact with external environment that consist of tightly packed cells with keratin (a protective protein)
what does mucous membranes do as a physical factor
consist of an epithelial layer and an underlying connective tissue layer
what does mucus do as a physical factor
slightly viscous glycoprotein
prevents drying out and traps microbes
what does ciliary escalator do as a physical factor
microbes trapped in mucus are transported away from the lungs via cough response or phlegm
what does saliva do as a physical factor
washes microbs off
what does urine do a s physical factor
cleanses the urethra and prevent colonization in the genitourinary tract
what does vaginal secretions do in regards to physical factors
move microorganisms of the body
what are the chemical factors for skin, gastric acid and vaginal secretions and what is the significant
low pH= very few microbs can survive
what is the chemical factor in sebum
fungistatic fatty acid
what does perspiration, tears, saliva, and urine have for a chemical factor
lysozyme (enzyme)
Summarize innate immunity (first line of defense, second line of defense) and adaptive immunity (third line of defense)
formed elements in blood
what are erthrocytes
red blood cells
formed elements in blood
what are leukocytes
white blood cells
formed elements in blood
what are the two classes of leukocytes
granulocytes and arganulocytes
what are the three types of granulocytes
neutrophils
basophils
eosinophils
what are the three types of agranulocytes
monocytes
dendritic cells
lymphocytes
what are the three types of lymphocytes
natural killer cells
T-cells
B-cells
what is the function of red blood cells
transport O2 and CO2
white blood cells
what is the function of neutrophils
phagocytosis
white blood cells
what is the function of basophils
histamine
white blood cells
what is the function of eosinophils
leave the blood to kill parasites
white blood cells
what is the function of monocytes
phagocytosis after maturation to macrophage
white blood cells
what is the function of dendritic cells
phagocytosis (derived from monocytes)
white blood cells
what is the function of natural killer cells
destroy target cells (cancer cells)
white blood cells
what is the function of T cells
cell mediated immunity
white blood cells
what is the function of B cells
produce antibodies
white blood cells
what is the function of platelets
blood clotting
what increases during certain kinds of infection in regards to white blood cells (name)
-leukocytosis
what decreases during certain kinds of infection in regards to white blood cells (name)
-leukopenia
what are the components of lymphatic system
consist of fluid (lymph) lymph vessels, lymphoid tissue, and red bone marrow
define phagocytosis
ingestion of microbes or particles by a cell, performed by phagocytes
what do phagocytosis do to attract
chemotaxis- chemical attractants
how do phagocytosis adhere
PAMPS and TLR
opsonization facilitaes adherence
how do phagocytosis ingest
psuedopods and phagosomes
how do phagocytosis digest
phagolysosome
define inflammation
caused by microbial infection physical agents and chemical agents
what are the 4 signs of inflammation
redness
swelling
pain
heat
what proteins are activated during early stages of inflammation
acute-phase proteins
what happens during inflammation in regards to vascular system
vascular dilate which increase flow and thinning of tissue
histamine, kinins, prostaglandins, and leukotrienes
what are the 3 stages of inflammation
1- vasodilation- dilation of blood vessels to increase blood flow to site of damage
2- phagocyte migration and phagocytosis- within an hour, neutrophils and monocytes begin to stick to the inner surface of he endothelium, then they migrate between the endothelial cell to reach damage site (diapedesis) phagocytize microbes and cell debris
3- tissue repair- damaged and dead cells are replaces. tissue types vary in ability to repair itself
