First Year Microbiology Practice Mid-term Questions

Capsules of bacteria primarily protect an organism from antibiotics.



Bacteria can have capsules that mimic self tissue



Bacteria may be able to degrade molecules that are chemotactic.



Some bacteria are capable of stopping MAC complex formation.



Some bacteria escape the immune response by becoming phagocytosed and
living within a cell after escaping the norma phagocytic pathway.









A-B toxins are not toxic until they are taken up by a cell and cleaved
into seperate components.



A superantigen is one that stimulates only T helper cells.



Endotoxin can be inactivated by brief boiling.



Exotoxins are proteins that may or may not be secreted by bacteria.



Exotoxins are more capable of generating a vigorous antibody response
than endotoxin.









Some viruses create fake MHC molecules on their surface which stop NK
cells from killing.



Some viruses avoid neutralizing antibodies by forming a syncytium with a
new cell.



Some viruses block surface expression of MHC molecules.



Some viruses can cause infection without binding and entering a target
cell.



Some viruses use antibodies to enhance their uptake by target cells.









A latent infection is one in which the pathogen is present but does not
cause symptoms.



In an organism with an ID50 of 100 is more likely to cause an infection
than an organism with an ID50 of 10.



An infection may not produce symptoms.



The incubation period is the time between introduction of an organism
and onset of symptoms.



A secondary infection is one that occurs as a result of a primary
infection.





























A.

Allow bacteria to bind to the cells lining the bladder.

B.

Allow bacteria to avoid opsonization by antibodies.

C.

Inactivates complement.

D.

Allows bacteria to kill phagocytes by forming pores in their membranes.

E.

Cleaves antibodies found in mucus and secretions.



Bottom of Form

A person can spread disease during the incubation period of an
infection.



Many things such as race, age and gender can influence the ability of a
person to become infected with a specific organism.



A vector is a living organism that can cause the spread of disease.



The most common reservoir for human diseases are humans.



An organism will cause the same disease regardless of if it enters via
your respiratory tract or through your skin.









Nosocomial infections can range from mild to life threatening.



Outbreaks of nosocomial infections have been traced to hospital
employees who are carriers of a specific pathogen.



Catheters that penetrate the skin can be portals for nosocomial
infections.



Handwashing between patients dramatically reduces incidence of
nosocomial infections.



The use of antibiotic has reduced the occurance of nosocomial
infections.









A pathogen that infects only humans are much more likely to be
controlled than a pathogen that can infect both humans and animals.



Herd immuity is the protection of non-immune individuals by the lack of
a reservoir of infection.



A reservoir can be dirt, desert and water.



Inhaled particles smaller than 10micrometers are usually trapped in the
mucus and swallowed.



Horizontal transmission of disease occurs during the transfer of a
pathogen via water or food.









education and research



contact lenses



day care centers



misuse of antibiotics



war





























A.

drinking glass, money, phones

B.

lakes, deserts, animals, humans

C.

a mosquito in which a parasite must complete part of it's life cycle.

D.

fly moving from food containing pathogen to a cut on the skin.

E.

acquiring rabies from infected animals.