micro bio exam 2 concept and sample questions

__________ facilities require that all manipulations be performed in a safety cabinet with HPA filtration.

BSL-3

The removal of all microbes in or on an object is known as

Sterilization

How does the alteration of a microbe’s cytoplasmic membrane by an antimicrobial agent lead to cell death?

Cellular contents will leak out of the cell, leading to cell death

What is the first thing you should do to control microbial growth on a surgical

instrument that is covered with blood?

Clean the blood off of the instrument, then proceed to sterilize it

___________ are antimicrobial chemicals produced naturally by microorganisms.

Antibiotics

Most antibiotics comes from what source?

Bacteria

The property of a chemical agent to be more inhibitory for a pathogen than for the pathogen’s host is referred to as

Selective toxicity

The mechanism of _____________ is to inhibit the formation of the peptidoglycan layer in the bacterial cell wall.

a. Penicillin

b. Cephalosporin

c. Beta-lactams

All of the above

What is one disadvantage associated with the use of broad-spectrum antibiotics?

They kill normal microbiota

What is the minimum inhibitory concentration (MIC)?

The smallest amount of drug that will inhibit the growth and

reproduction of a pathogen

What is a pleomorphic prokaryote?

A prokaryote whose cell morphology varies in shape and size

________ form when planes of cell division are random.

Staphylococci

All are taxonomic domains except

Protista

Which of the following does not have a high G+C content?

Lactobacillus

Which of the following is not a characteristic of pseudomonads?

They are in the deltaproteobacteria group

Which of the following are not eukaryotic microbes?

Archaea

__________ is the free-living, motile feeding stage of protozoa.

Trophozoite

Which group of protozoa is unique because they lack mitochondria, peroxisomes, and Golgi bodies?

d. Diplomonadida

Alveolates are named as such due to their

Membrane-bound cavity

How many legs do arachnids have as adults?

4 pairs of legs

an organism that utilized an inorganic source of carbon as its sole carbon source and light as its energy source is a

Photoautotroph

___________ require oxygen levels between 2% and 10%.

d. Microaerophiles

What must be done to a sample before the pour-plate technique is performed?

Colony-forming units must be separated by performing serial dilutions

acConkey agar selects for ______ microbes and is differential based on __________.

Gram-negative … lactose fermentation

What is the best method for storing bacterial cultures for 10 years or longer?

Lyophilization