Lecture Exam 2 Flashcards
Viruses have some of the properties of cellular life forms. Which of the following is not a characteristic of viruses
Grow in response to their environmental conditions
Which of the following structures do animal viruses use to attach themselves and enter the host cells?
Viral spikes
A naked virus
Has no envelope
Viruses that have plus strand RNA chromosomes that act as a template for DNA synthesis are known as:
Proviruses
Acquired immune deficiency Syndrome (AIDS is caused by a retrovirus. Which of the following best represents it
RNA-DNA- mRNA- protein
Which of the following represents the correct order of steps in a typical virus replication cycle?
Adsorption - penetration - synthesis- maturation- release
Organisms which get their carbon from other organisms are:
Heterotrophs
Enzymes work by:
Decreasing the activation energy of the reaction
An enzyme-substrate complex forms when substrate binds to an enzyme at the enzyme’s ____ site.
Active
Competitive inhibition of enzymes occurs when the inhibitors:
Changes the shape of the enzyme
Sulfa drugs bind to the active site of the enzyme which normally converts para-amino benzoic acid (PABA to folic acid, preventing the production of folic acid and eventually purine synthesis. In this case, the sulfa drug is acting as a/an:
Competitive inhibitors
Influenza’s RNA genome mutates frequently causing minor changes to the HA and NA spikes called
Antigenic Drift
Enzymes are affected by heat and ph
True
Which of the following statements about enzyme inhibition is true?
No competitive inhibitors bi d to several different sites on an enzyme
In glycolysis ____ molecules of pyruvic acid are produced
Two
Which of the following is true about glycolysis?
The net yield of ATP is two ATPs
Pyruvic acid is metabolized in the absence of oxygen during the process of:
Fermentation
The single strand positive sense RNA in animal virus is similar to mRNA and can start making protein as soon as it infects the host cell
True
The mode of action of an antimicrobial agent refers to
How it exert its effects upon microorganisms
Selective toxicity
Harms microbes without significantly harming the host
Side effects due to antimicrobial agents are:
a. Allergic reactions
b. Toxicity
c. Disruption of microbial flora
d. All of the above
All of the above
Mechanism of bacterial resistance to antimicrobial agents include all of the following except:
Alteration of normal microflora
Destruction or inactivation of antimicrobial agents is an example of what kind of bacterial resistance mechanism?
Enzyme development
Mutation of DNA that produces an altered ribosomes is an example of what type of bacterial resistance mechanism?
Alterations target
A microorganism that can cause ready-made folic acid from its environment and no longer needs to synthesize it from the PABA precursor demonstrates what type of antimicrobial resistance organism?
Alteration of an enzyme
Because the tetracyclines are effective against a large variety of different organisms they are considered to:
Be broad spectrum drugs
Waterborne transmission of pathogens involving water contaminated by raw sewage is an example of what mode of transmission?
Droplet nucleic
Pathogens that are delivered by insects follow what mode of disease transmission?
Vector borne
Which of the following pertain to food borne transmission of infectious agents?
Unsanitary food preparation
Sexually transmitted disease are most often spread by what mode of transmission?
Direct contact
Zoonosis refers to an infectious disease that is transmitted:
From human to their pets
A bacteria that is transformed:
Has acquired naked DNA from the environment
The transfer of DNA between bacterial cells by a virus is:
Conjugation
