Class notes
Class Notes: Lecture 1 of M118L at UCI
- Institution
- University Of California - Irvine
Notes cover lecture 1A and 1B videos of M118L course at UCI. Includes lecture's practice problems.
[Show more]
Seller
Follow
Content preview
Lecture 1 (covers videos A & B) Abbreviations:Tuesday, January 5, 2021 8:36 PM Ex. = for example,
b/w = between
b/c = because
w/ = with
1. Explain the enrichment process that will be used to obtain bacterial isolates. Lab Walkthrough – Bacterial Isolation
2. Classify a given type of media based on its ingredients. • In this class, students will perform 2 different bacteria isolations:
3. State the importance of sterile technique and be able to follow these rules in lab. 1. Anal isolation: get intestinal bacteria.
4. Describe significance of various steps of Gram Staining. 2. Soil isolation: to get bacteria that secrete a fluorescent pigment.
• Culture media: medium used to grow microorganisms on/in. Ex. Agar plates, liquid • For successful isolation, a good sterile technique is needed.
media. • Quadrant streaking technique: section 4 areas on an agar plate (draw 3 lines in a
○ Essential nutrients present: carbon and nitrogen source, vitamins, amino acids. checkered pattern).
○ Defined media: composition of media is known. (What component, how much, ○ Sterile stick: for every quadrant, use a new stick. Rub some of the bacteria onto
etc.) the stick and then smear on one section of the plate. Using a new stick, touch the
○ Complex media: at least one component is unknown within the composition. bacteria in the corner a Q1 and spread it over Q2. Repeat for Q3 and Q4. For Q4,
○ Selective media: media that contains something that inhibits a particular do not use overlapping strokes.
organism's growth. Ex. High-salt media -> Osmotic pressure -> media is ○ Sterile loop: Rub some of the bacteria onto the sterile loop and then smear on one
selecting for organisms that can survive the osmotic stress! quadrant of the plate. Re-sterilize the loop w/ heat; wait for loop to cool down!
○ Enriched media: media that contains growth factor, or something essential for a Using the newly sterilized loop, touch the bacteria in the corner a Q1 and spread it
certain organism to grow. Ex. Media w/ sheep's blood -> excess nutrients over Q2. Repeat for Q3 and Q4. For Q4, do not use overlapping strokes.
○ Differential media: media that contains something that allows you to distinguish • To get a pure culture, student needs to get individual colonies. ->
b/w 2 or more types of bacteria. Ex. Media w/ pH indicator -> can indicate a • To get single colonies on a plate, student needs to dilute a culture b/c colony formation
certain bacteria on a non-buffered(can resist pH changes) media. requires cells to be far apart.
• Both organisms are surviving, and we can observe a difference b/w them. • Once bacterial colony is isolated, student must identify bacteria using Gram Stains.
• Gram stains: differentiate b/w gram positive(purple) and gram negative(pink).
The benefits of buying summaries with Stuvia:
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
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
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 PrinceAlixD. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $2.99. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
67096 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now