Medium Culture – Microbiology Exam
The key terms of Microbiology Exam include, Cell, Bacteria, Medium, Culture.
A(n) ______ stain sticks to cells because of its opposite charge.
negative
neutral
Basic – correct
acidic
Table 6.1
Three different culture media
| Medium A | Medium B | Medium C |
| Na2HPO4 | yeast extract | glucose |
| KH2PO4 | Na2HPO4 | peptone (protein extract) |
| MgSO4 | KH2PO4 | (NH4)2SO4 |
| CaCl2 | MgSO4 | KH2PO4 |
| NaHCO3 | (NH4)2SO4 | Na2HPO4 |
In Table 6.1, which medium (media) is/are chemically defined, a.k.a. synthetic?
C
B & C
A & B
B
A – correct
Which of the following is not a distinguishing characteristic of prokaryotic cells?
They have a single circular chromosome.
Their DNA is not associated with many proteins.
They often have cell walls often containing peptidoglycan.
They have a plasma/cell membrane – correct
They lack membrane-enclosed organelles.
The term for a line-like aggregation of prokaryotic cells is:
Strepto – correct
sarcina
tetrad
staphylo-
diplo-
Which of the following tools is used to transfer a very small amount, about 10 microliters (ul) or less, of a liquid culture to another container?
small graduated cylinder
syringe and needle
loop
needle
Pipet – correct
Explanation
Note the word “about”, that means the measurement is not precisely 10 ul. Also a pipet can’t measure that small an amount, one needs to use a micropipet/micropipettor which is a different tool.
A major difference between a transmission electron microscope (TEM) and a scanning electron microscope (SEM) is in the:
number of electrons used
colors of the images produced
level of technical skill of the user
type of lenses
interaction of electron beam and the specimens – correct
Using a microscope, you observe a microbe moving toward a food source. This is an example of:
responsiveness/irritability – correct
reproduction
cellular structure
evolution of the lineage
A bacterial colony on an streak plate comes from:
one cell in the original sample – correct
a small number of cells in the original sample
a large number of cells in the original sample
A culture medium on which the O:157:H7 strain of E. coli is black and all others are white is called a(n):
selective medium
enrichment culture
differential medium and enrichment culture
differential medium – correct
selective medium and differential medium
A(n) ______ stain sticks to cells because of its opposite charge.
negative
neutral
Basic – correct
acidic
Table 6.1
Three different culture media
| Medium A | Medium B | Medium C |
| Na2HPO4 | yeast extract | glucose |
| KH2PO4 | Na2HPO4 | peptone (protein extract) |
| MgSO4 | KH2PO4 | (NH4)2SO4 |
| CaCl2 | MgSO4 | KH2PO4 |
| NaHCO3 | (NH4)2SO4 | Na2HPO4 |
In Table 6.1, which medium (media) is/are chemically defined, a.k.a. synthetic?
C
B & C
A & B
B
A – correct
Which of the following is not a distinguishing characteristic of prokaryotic cells?
They have a single circular chromosome.
Their DNA is not associated with many proteins.
They often have cell walls often containing peptidoglycan.
They have a plasma/cell membrane – correct
They lack membrane-enclosed organelles.
The term for a line-like aggregation of prokaryotic cells is:
Strepto – correct
sarcina
tetrad
staphylo-
diplo-