BMSC 210 -Study Guide-UofS-Test
Questions and All Solved Solutions.
3 micro environments of the skin. - Answer - Dry
- Moist
- Sebacious glands
Dry Skin - Answer Mainly colonized by Betaproteobacteria and Corynebacteria
Moist Skin - Answer Mainly colonized by Corynebacteria and Staphyococci
Sebaceous Skin - Answer Mainly colonized by Propionibacteria
Oral Cavity - Answer - Complex heterogeneous microbial habitat
- Saliva contains antimicrobial enzymes
- High concentration of nutrients near surfaces promote localized microbial growth
- most abundant bacteria is lactic acid bacteria, Streptococci.
Tooth - Answer - Mineral matrix (enamel) surrounding living tissue (dentin and pulp)
- Bacteria colonize surfaces by first attaching to acidic Glycoproteins deposited by saliva.
Human microflora - Answer - Complex microbial community
- most organisms are facultatively aerobic
- some obligately anaerobic
- some obligately aerobic
- most abundant genus, streptococcus
What causes dental carries? - Answer As dental plaque accumulates the microorganisms
produce high concentrations of acid that results in decalcification of the tooth enamel.
Bacteria common to dental carries. - Answer - lactic acid bacteria, Streptococcus Sobrinus, and
Streptococcus Mutans.
Human Gastrointestinal Tract - Answer - Consists of the Stomach, small intestine, and large
intestine.
,- Responsible for digestion of food, absorption of nutrients and production of nutrients by the
indigenous microbial flora.
Microflora of the Gastrointestinal Tract - Answer - influenced by physical condition of the area
- acidity of stomach and duodenum prevents many organisms from colonizing.
Intestinal microorganisms - Answer Carry out a variety of essential metabolic reactions that
produce various compounds
Type and amount of products produced is influenced by the composition of the microflora and
diet.
Upper respirator tract - Answer Sinuses
Nasopharynx
Pharynx
Oral cavity
Larynx
Lower respiratory tract - Answer Trachea
Bronchi
Lungs
Common microflora of upper respiratory tract - Answer Staphylococci, streptococci,
diphtheroid Bacilli, and other gram negative cocci.
Common microflora of lower respiratory tract - Answer Should be very little to no microflora
present in a healthy individual.
The bladder - Answer Typically sterile in both men and women.
Changes in conditions such as pH can sometimes allow for infectious pathogens to enter
through the urethra.
E. Coli and Proteus Mirabilis are common causes of urinary tract infections in women.
The adult female Vagina - Answer Weakly acidic and contains significant amounts of glycogen.
Glycogen is produced by resident organism Lactobacillus Acidophilus, which ferments glycogen,
producing lactic acid.
Pathogens: - Answer Microbial parasites
, Pathogenicity: - Answer The ability of a parasite to inflict damage on the host
Virulence: - Answer Measure of pathogenicity
- the relative ability of a pathogen to cause disease
Opportunistic pathogen: - Answer Causes disease only in the absence of normal host
resistance
Infection: - Answer Situation in which a microorganism is established and grown in a host,
whether or not the host is harmed.
Disease: - Answer Damage or injury to the host that impairs host function.
Methods to measure Virulence - Answer - experimental studies of Lethal Dose 50 (LD50)
Lethal dose 50: - Answer The amount of an agent that kills 50% of the animals in a test group.
Toxicity: - Answer Ability of a microorganism to cause disease as a result of a preformed toxin
that inhibits host function or kills host cells.
Invasiveness: - Answer Ability of a pathogen to grow in host tissue at densities that inhibit host
function
Can cause damage without producing a toxin
Attenuation: - Answer Decrease or loss of of virulence used to produce vaccines for certain
pathogens.
First step to infection - Answer Adherence
Mediators of bacterial adherence - Answer - Extracellular macromolecules that are not
covalently attached to the bacterial cell surface. E.g. Slime layer, capsule
- Fimbriae and pili: attach to cell surface glycoproteins
Second step of infection - Answer Colonization
Bactermia: - Answer The presence of bacteria in the bloodstream
Questions and All Solved Solutions.
3 micro environments of the skin. - Answer - Dry
- Moist
- Sebacious glands
Dry Skin - Answer Mainly colonized by Betaproteobacteria and Corynebacteria
Moist Skin - Answer Mainly colonized by Corynebacteria and Staphyococci
Sebaceous Skin - Answer Mainly colonized by Propionibacteria
Oral Cavity - Answer - Complex heterogeneous microbial habitat
- Saliva contains antimicrobial enzymes
- High concentration of nutrients near surfaces promote localized microbial growth
- most abundant bacteria is lactic acid bacteria, Streptococci.
Tooth - Answer - Mineral matrix (enamel) surrounding living tissue (dentin and pulp)
- Bacteria colonize surfaces by first attaching to acidic Glycoproteins deposited by saliva.
Human microflora - Answer - Complex microbial community
- most organisms are facultatively aerobic
- some obligately anaerobic
- some obligately aerobic
- most abundant genus, streptococcus
What causes dental carries? - Answer As dental plaque accumulates the microorganisms
produce high concentrations of acid that results in decalcification of the tooth enamel.
Bacteria common to dental carries. - Answer - lactic acid bacteria, Streptococcus Sobrinus, and
Streptococcus Mutans.
Human Gastrointestinal Tract - Answer - Consists of the Stomach, small intestine, and large
intestine.
,- Responsible for digestion of food, absorption of nutrients and production of nutrients by the
indigenous microbial flora.
Microflora of the Gastrointestinal Tract - Answer - influenced by physical condition of the area
- acidity of stomach and duodenum prevents many organisms from colonizing.
Intestinal microorganisms - Answer Carry out a variety of essential metabolic reactions that
produce various compounds
Type and amount of products produced is influenced by the composition of the microflora and
diet.
Upper respirator tract - Answer Sinuses
Nasopharynx
Pharynx
Oral cavity
Larynx
Lower respiratory tract - Answer Trachea
Bronchi
Lungs
Common microflora of upper respiratory tract - Answer Staphylococci, streptococci,
diphtheroid Bacilli, and other gram negative cocci.
Common microflora of lower respiratory tract - Answer Should be very little to no microflora
present in a healthy individual.
The bladder - Answer Typically sterile in both men and women.
Changes in conditions such as pH can sometimes allow for infectious pathogens to enter
through the urethra.
E. Coli and Proteus Mirabilis are common causes of urinary tract infections in women.
The adult female Vagina - Answer Weakly acidic and contains significant amounts of glycogen.
Glycogen is produced by resident organism Lactobacillus Acidophilus, which ferments glycogen,
producing lactic acid.
Pathogens: - Answer Microbial parasites
, Pathogenicity: - Answer The ability of a parasite to inflict damage on the host
Virulence: - Answer Measure of pathogenicity
- the relative ability of a pathogen to cause disease
Opportunistic pathogen: - Answer Causes disease only in the absence of normal host
resistance
Infection: - Answer Situation in which a microorganism is established and grown in a host,
whether or not the host is harmed.
Disease: - Answer Damage or injury to the host that impairs host function.
Methods to measure Virulence - Answer - experimental studies of Lethal Dose 50 (LD50)
Lethal dose 50: - Answer The amount of an agent that kills 50% of the animals in a test group.
Toxicity: - Answer Ability of a microorganism to cause disease as a result of a preformed toxin
that inhibits host function or kills host cells.
Invasiveness: - Answer Ability of a pathogen to grow in host tissue at densities that inhibit host
function
Can cause damage without producing a toxin
Attenuation: - Answer Decrease or loss of of virulence used to produce vaccines for certain
pathogens.
First step to infection - Answer Adherence
Mediators of bacterial adherence - Answer - Extracellular macromolecules that are not
covalently attached to the bacterial cell surface. E.g. Slime layer, capsule
- Fimbriae and pili: attach to cell surface glycoproteins
Second step of infection - Answer Colonization
Bactermia: - Answer The presence of bacteria in the bloodstream
