BIO251 Microbiology
Midterm Exam Review
Qns & Ans
2025
, Question 2 pts
A researcher is asked to determine if a sample contains Neisseria
meningitides. Knowing Neisseria meningitides is slow growing and
other foreign microbes may also be present in the culture, which type of
media would be best suited?
Correct! Selective media
Selective media. If additional foreign microbes may be present in
your sample and you know Neisseria meningitides is slow growing,
you must restrict the unwanted microbes while supporting the growth
of Neisseria meningitides. Thus, you are selectively encouraging one
microbes growth, while selectively restricting others.
Differential media
Growth media
Selective and Differential media
Question 3 pts
What are the requirements of a fastidious microbe?
Your Answer:
A fastidious microbe requires a specific and complex set of essential
nutrients to grow. Enriched media contains the essential nutrients
needed for the specific subset of microorganisms to grow and survive.
, A fastidious microbe is an organism with complex growth
requirements such that if absent it will not grow. Enriched
medias thus contain these specific and essential nutrients
required for the growth of a particular subset of
microorganisms.
Question 4 pts
True or False: LB agar is classified as a selective, non-differential
media.
True
Correct! False
LB agar is the most basic type of agar and like LB media supports
the growth of virtually all microbes without restriction.
Question 5 pts
The polysaccharide-based hardening agent added to LB media to
produce LB agar is derived from what?
Your Answer:
, seaweed extract
Seaweed (algae) extract.
Question 6 pts
Blood agar is which type of medium? Select all that apply.
Selective and Differential
Correct! Enriched
Selective
Correct!
Differential
Blood agar can be used to differential between species based on its
hemolytic activity.
Question 7 pts
Midterm Exam Review
Qns & Ans
2025
, Question 2 pts
A researcher is asked to determine if a sample contains Neisseria
meningitides. Knowing Neisseria meningitides is slow growing and
other foreign microbes may also be present in the culture, which type of
media would be best suited?
Correct! Selective media
Selective media. If additional foreign microbes may be present in
your sample and you know Neisseria meningitides is slow growing,
you must restrict the unwanted microbes while supporting the growth
of Neisseria meningitides. Thus, you are selectively encouraging one
microbes growth, while selectively restricting others.
Differential media
Growth media
Selective and Differential media
Question 3 pts
What are the requirements of a fastidious microbe?
Your Answer:
A fastidious microbe requires a specific and complex set of essential
nutrients to grow. Enriched media contains the essential nutrients
needed for the specific subset of microorganisms to grow and survive.
, A fastidious microbe is an organism with complex growth
requirements such that if absent it will not grow. Enriched
medias thus contain these specific and essential nutrients
required for the growth of a particular subset of
microorganisms.
Question 4 pts
True or False: LB agar is classified as a selective, non-differential
media.
True
Correct! False
LB agar is the most basic type of agar and like LB media supports
the growth of virtually all microbes without restriction.
Question 5 pts
The polysaccharide-based hardening agent added to LB media to
produce LB agar is derived from what?
Your Answer:
, seaweed extract
Seaweed (algae) extract.
Question 6 pts
Blood agar is which type of medium? Select all that apply.
Selective and Differential
Correct! Enriched
Selective
Correct!
Differential
Blood agar can be used to differential between species based on its
hemolytic activity.
Question 7 pts
