Questions and Answers
What type of medium contains blood, serum, or other special growth factors, and what type of bacterial growth is supported by this medium?
Agar is an important component of media because ________.
A fastidious organism must be grown on/in what type of medium?
A pure culture contains ________.
Signup and view all the answers
True or False: The thinner peptidoglycan layer of gram-positive bacteria allows the crystal-violet-iodine complex to leave the cell.
Signup and view all the answers
When ethanol is applied correctly, gram-positive cells appear _______ and gram-negative cells appear ________.
Signup and view all the answers
After Gram's iodine is added, what color do the cells appear under a light microscope?
Signup and view all the answers
Why must fresh cells be used when performing a Gram stain?
Signup and view all the answers
The differential stage of the Gram stain is the application of _______.
Signup and view all the answers
If the Gram's iodine step was skipped in the Gram stain procedure, what color would the cells likely be when viewed under the microscope?
Signup and view all the answers
True or False: All bacteria can be classified as either gram-positive or gram-negative.
Signup and view all the answers
True or False: The presence of flagella can be determined by a Gram stain.
Signup and view all the answers
Rod-shaped bacteria _______.
Signup and view all the answers
True or False: Bacteria are larger than human cells.
Signup and view all the answers
True or False: Bacteria are only visible with an electron microscope.
Signup and view all the answers
The term used to describe a cluster of spherical bacteria is _______.
Signup and view all the answers
What general type of stain is used to separate types of bacteria based on their cellular structures?
Signup and view all the answers
The specimen preparation that is best for viewing cell motility is ________.
Signup and view all the answers
Which type of medium is able to distinguish different species or types of microorganisms based on an observable change in the colonies or in the medium?
Signup and view all the answers
What is the term for when a patient specimen is spread onto several types of culture media?
Signup and view all the answers
What is it called when culture media are placed at the proper growth temperature and allowed time to grow?
Signup and view all the answers
What term describes the process of spreading a colony onto a new plate of media using a quadrant streak method?
Signup and view all the answers
What does inspection involve during colony growth observation?
Signup and view all the answers
What is the term for using a variety of biochemical tests to characterize a microbe?
Signup and view all the answers
True or False: At the end of the Gram stain, gram-positive bacteria will be seen as red/pink cells.
Signup and view all the answers
In a _______ stain, the dye stains the background, forming a silhouette around the unstained organism.
Signup and view all the answers
_____ involves placing a sample into a container of fresh medium.
Signup and view all the answers
Multiplication of an organism in a culture is promoted by ______.
Signup and view all the answers
Pour plating, streak plating, and spread plating are _____ methods for separating individual microbes from each other.
Signup and view all the answers
_____ involves the observation of macroscopic and microscopic characteristics of microbes in samples.
Signup and view all the answers
Biochemical, immunological, and genetic testing assist the microbiologist in _____ so that a final _____ can be made.
Signup and view all the answers
What is the term describing any procedure that applies dye to a specimen smear?
Signup and view all the answers
What is the most universal diagnostic staining technique used for bacterial identification and classification?
Signup and view all the answers
The Gram stain, which employs different colored dyes to analyze bacterial cell wall structure, is an example of which type of staining method?
Signup and view all the answers
What unique component of the outer membrane of gram-negative bacteria acts as an endotoxin, causing symptoms of shock?
Signup and view all the answers
Match the staining technique to the appropriate example.
Signup and view all the answers
A nutrient medium that contains at least one ingredient that is NOT chemically definable would be termed _____.
Signup and view all the answers
The purpose of staining cells on a microscope slide is to ________.
Signup and view all the answers
What is the name of the sterile substance that allows for microorganism multiplication?
Signup and view all the answers
Which of the following are physical types of media along with liquid?
Signup and view all the answers
Which term best describes the patient's urine culture growth observed on a medium containing growth factors and complex nutrients?
Signup and view all the answers
What term describes the technique the RN must utilize during specimen collection to ensure a proper culture?
Signup and view all the answers
What term describes the process when the lab introduces the sample into a medium with the appropriate nutrients?
Signup and view all the answers
What term describes the process where visible growth is noted after storing the culture at the proper growth temperature for three days?
Signup and view all the answers
During the inspection of colony growth characteristics, all the following are macroscopically observed characteristics except _______.
Signup and view all the answers
Study Notes
Culture Media and Bacterial Growth
- Enriched media support the growth of fastidious bacteria by containing blood, serum, or special growth factors.
- Agar provides a solid surface for bacterial growth, making it essential for culturing microbes.
- Fastidious organisms require enriched media for successful cultivation.
Pure Cultures and Gram Staining
- A pure culture consists of only one species of microorganism, critical for accurate analysis.
- Gram-positive bacteria retain the crystal-violet-iodine complex, while gram-negative bacteria do not due to a thinner peptidoglycan layer.
- After iodine treatment, all cells appear purple under a microscope if the Gram stain is performed correctly.
- Fresh cells are necessary for Gram staining, as older cells may not retain the dye effectively.
Color Changes in Gram Staining
- Ethanol application results in purple for gram-positive cells and colorless for gram-negative cells.
- Skipping the iodine step would lead gram-negative cells to appear red/pink under the microscope.
Bacterial Characteristics and Classification
- Not all bacteria are classified as gram-positive or gram-negative; some do not fit this dichotomy.
- The presence of flagella cannot be determined through Gram staining alone.
- Rod-shaped bacteria can be either gram-positive or gram-negative; their shape does not determine staining characteristics.
Staining Techniques and Methods
- The differential stain technique is used to differentiate types of bacteria based on structural differences.
- A negative stain colors the background, revealing unstained organisms.
- Gram staining is the most universal diagnostic technique for bacterial identification.
- Staining enhances visibility, contrast, and aids in the study of microbial motility and structure.
Steps in Microbial Culture
- Inoculation involves introducing a sample to a nutrient medium to promote growth.
- Incubation allows cultures to grow at proper temperatures.
- Isolation aims to separate individual microbes using methods like quadrant streaking.
- Inspection includes observing characteristics of colonies and preparing Gram stains.
- Identification employs various biochemical tests for microbial characterization.
Physical Types of Culture Media
- Different media types include solid (non-convertible), semisolid, and liquid, essential for varied laboratory applications.
- Enriched media facilitate microbial growth through complex nutrients and growth factors.
Sterility and Sample Collection
- During collection from invasive lines, a sterile technique is critical to avoid contamination and ensure accurate culture results.
- The process of inoculating a culture medium allows microorganisms to multiply under controlled conditions.
Observational Characteristics of Microbes
- Colony characteristics for inspection include size, texture, and color but not cell shape, which is a microscopic feature.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your knowledge with these flashcards focused on microbiology concepts. Each card presents a question on growth media and bacterial types, helping you understand the nuances of microbiological growth conditions. Perfect for students looking to reinforce their understanding of microbiological principles.
