100% satisfaction guarantee Immediately available after payment Both online and in PDF No strings attached
logo-home
Previously searched by you
Previously searched by you
logo
Chapter21 Question and answers 100% correct $13.99   Add to cart
Quickly navigate to
Preview
  2.  
  3. Microbiology
  4.  
  5. Microbiology

Exam (elaborations)

Chapter21 Question and answers 100% correct

 7 views  0 purchase
  • Course
  • Microbiology
  • Institution
  • Microbiology

Chapter21 Question and answers 100% correct Chapter 6-Microbiology What are the physical requirements for microbial growth? - correct answer Temperature, pH, and osmotic pressure Temperature - correct answer Most microorganisms grow well at the temperatures that humans favor; but there a...

[Show more]

Preview 3 out of 17  pages

Document information

  • August 11, 2024
  • 17
  • 2024/2025
  • Exam (elaborations)
  • Questions & answers

Subjects

  • chapter21
  • chapter21 question and answers 100 correct

Written for

  • Microbiology
  • Microbiology

Seller

avatar-seller
Carzola98

Reviews received

Content preview

Chapter 6-Microbiology
What are the physical requirements for microbial growth? - correct answer
✔Temperature, pH, and osmotic pressure


Temperature - correct answer ✔Most microorganisms grow well at the
temperatures that humans favor; but there are three major ranges of
temperature: psychorophiles, meosphiles, thermophiles


psychorophiles - correct answer ✔cold-loving microbes (-10 to 20)


Mesophiles - correct answer ✔moderate-temperature loving microbes (10 to
50)


Thermophiles - correct answer ✔heat loving microbes (40 to 73)


Maximum growth temperature - correct answer ✔highest temperature at
which growth is possible


optimum growth temperature - correct answer ✔temperature at which the
species grows back


minimum growth temperature - correct answer ✔lowest temperature at which
the species will grow


Typically the max and min growth temperatures are only about 30 degrees
Celsius apart

,psychotrophs - correct answer ✔food microbiologists favor, this group is
known for spoilage of food


Why refrigerate? - correct answer ✔based on the principle that microbial
reproduction rates decrease at low temperatures (or entirely dormant)


hyperthermophiles or extreme thermophiles - correct answer ✔arcahe; have
an optimum growht temperature of 80* C or more; live in hot springs and
sulfur important in their metabolic activity


What pH do bacteria typically grow in? - correct answer ✔neutrality (between
6.5 adn 7.5)
Cutlured bacteria often produce acids that eventualy interfere with their own
growth; chemical buffers must be included in growth medium


acidophiles - correct answer ✔remarkably tolerant of acidity


How do most microorganisms obtain all their nutrients? - correct answer
✔through solution from their surrounding water; thus they require water for
growth;


How does high osmotic pressure effect bacteria? - correct answer ✔When
concentration of solutes is higher in the cell (hypertonic)


When concentration of solutes is higher outside the cell - correct answer
✔Cell will shrink, removes necessary water


Plasmolysis - correct answer ✔shrinkage of the cell cytoplasm

, Plasma membrane pulls away from the cell wall; addition of salts to a solution
will increase osmotic pressure (can be used for food preservation)


Extreme Halophiles - correct answer ✔adapted well to high salt
concentrations that they actually require them for growth


Obligate halophiles - correct answer ✔require salt for growth


Facultative halophiles - correct answer ✔do not require high salt
concentrations but are able to grow in salt concentrations up to 2%; few can
tolerate even up to 15%


Typical medium composed of? - correct answer ✔1.5% agar, the rest is
water!; if all water, the enviornment is hypotonic, water will move into the cell-
lyses


What are the chemical requirements of microbial growth? - correct answer
✔carbon, nitrogen, suflur, phosphorus, trace elements, oxygen, and organic
growth factors


Why carbon? - correct answer ✔one of the most important requirements for
microbial growth; carbon is the structural backbone of living matter; it is neeed
for all organic ompounds that make up a living cell; half of the dry weight of a
living cell is carbon


Chemoheterotrophs - correct answer ✔get most of their carbon from the
source of their energy


Nitrogen, sulfur, phosphorus - correct answer ✔DNA and RNA and ATP
synthesis: require nitrogen and phosphorous

The benefits of buying summaries with Stuvia:

Guaranteed quality through customer reviews

Guaranteed quality through customer reviews

Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.

Quick and easy check-out

Quick and easy check-out

You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.

Focus on what matters

Focus on what matters

Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!

Frequently asked questions

What do I get when I buy this document?

You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.

Satisfaction guarantee: how does it work?

Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.

Who am I buying these notes from?

Stuvia is a marketplace, so you are not buying this document from us, but from seller Carzola98. Stuvia facilitates payment to the seller.

Will I be stuck with a subscription?

No, you only buy these notes for $13.99. You're not tied to anything after your purchase.

Can Stuvia be trusted?

4.6 stars on Google & Trustpilot (+1000 reviews)

76449 documents were sold in the last 30 days

Founded in 2010, the go-to place to buy study notes for 14 years now

Start selling
$13.99
  • (0)
  Add to cart