microbiology lab

Serial dilution

A method used to dilute a substance in a stepwise manner into a solution with a constant dilution factor is known as?

A fundemental technique important in the laboratory and used by Microbiologists for a variety of procedures such as, transferring cultures, inoculating media and isolation of pure cultures is known as?

Aseptic technique

One difference between the two techniques is that the "Spread Plate Method " is used to evenly distribute the bacteria across the entire plate and a similarity is the end result should produce pure colonies in both methods.

Concerning the inoculation techniques discussed in this lab, one difference between the "Spread Plate Method" and the "Streak Plate Method of Isolation" is___________ and one similarity is_________?

Contain specific dyes that cause a color change as different bacteria grow and produce waste products.

Differential media is a type of specialty media which?

Global Harmonized System

The new GHS system provides information on the labels of the chemicals that you will use in lab. What does GHS stand for?

differential

This agar plate was only inoculated with one species of bacteria. This type of agar can best be described as___________ because of the distinct coloration of the bacteria.

Beta hemolysis

This is due to the lysis of red blood cells, in Blood Agar, and the complete absorbance of the nutrients from the red blood cells, leaving behind a clear zone on the agar.

beta hemolysis

This is the complete lysis of red blood cells on blood agar where all of the contents of the cell were consumed as a nutritional source

a growth inhibitor was used and resulted in no growth of one of the species. the color change occurred due to a dye or indicator that was added to the media during preparation.

This specialty media was inoculated with 3 different species of bacteria (one type in each zone). Based on these results________________.

You will be asked to leave the laboratory.

What will be the result if you fail to wear closed to shoes in the laboratory?

These results would be inaccurate because the extra culture on the inside and outside of the pipette would increase the concentration of the next tube beyond the factored amount.

When performing a serial dilution, a student forgot to change the pipette and used the same pipette for every .5 mL transfer of the solution from tube to tube. Would these results be accurate and what would you predict the outcome would be?

Wet your hands, apply soap, rub hands together while singing Happy Birthday twice, rinse well and dry, use the paper towel to turn off the faucet.

Which of the below is the correct procedure for washing your hands?

You must wear a long sleeve shirt or blouse under your lab coat when in the lab.

Which of the following is NOT a requirement for laboratory clothing?

Selective and Differential

Zone 1, 2 and 4 on this plate demonstrate 4+ growth. There is no growth on zone 3. Based on the results of this agar plate, this type of media could best be described as?

True

According to the syllabus for this lecture and lab section (BCS 200) missing more than 3 labs will result in receiving a grade of F in the course.

True

According to the syllabus for this lecture and lab section (BCS 200) you must attend both lab periods (Day 1 and Day 2) to receive credit for attendance.

This was not an accurate serial dilution because the number of colonies counted on the 1:100,000 plate was not within the target window and the difference in the count between the two plates was not close to a factor of 10.

After performing a serial dilution a student counted 9 colonies on the 1:100,000 plate and 21 colonies on the 1:10,000 plate. Was this an accurate serial dilution? Why or why not?

The acronym for the use of a fire extinguisher is PASS. Which one of the statements below is correctly stated for using this acronym?

Aim at the base of the fire

selective and differential

An agar that contains a dye and/or indicator and a growth inhibitor as part of its ingredients can best be described as.

Proper aseptic technique prevents contamination of cultures from foreign bacteria inherent in the environment. Correct! Using proper aseptic technique can greatly minimize or even eliminate the risk of contamination. Correct! Aseptic technique prevents microbes used in the laboratory from accidentally being released into the environment and/ or infecting people working in the laboratory.

Aseptic technique is a fundamental and important laboratory skill in the field of microbiology. Choose some examples of how or why aseptic technique would be used in a laboratory. Choose all that apply.

gamma hemolysis

Bacteria is growing on the agar but there is no change in the appearance or color of the blood agar and no lysis of red blood cells

19,000,000 cfu/mL

In a serial dilution, the final dilution factor performed was 1:100,000. After 48 hours incubation @ 37oC there were 190 colonies counted on the plate. What was the concentration of bacteria in the original undiluted sample?

10

In the serial dilution procedure of this laboratory exercise the dilution was increased with each transfer to the next tube by a factor of________?

beta hemolysis

In this type of hemolysis a clear zone is left behind in the agar

False

Patient samples, after specimen collection, that were transported promptly but inaccurately labeled will be tested anyway.

Samples must be collected using proper collection techniques. Collected samples must be transported to the laboratory as soon as possible. It must be collected in the presence of the patient and labeled with 2 identifiers (such as patient name and number). It must be collected in the proper container

List 4 protocols that must be followed for the collection of a biological specimen in order to obtain a timely and valid laboratory result.

alpha hemolysis

Lysis of red blood cells occurs but the iron in the RBC is not consumed as a food source

a. Gram negative species b. Lactose fermentation

MacConkey agar (MAC) is most commonly used for the selective isolation of (a.)_____________ and differentiate them based on (b.)____________ resulting in a color change. Choose one answer for each letter

True

Students may attend and participate in the laboratory exercises on the first scheduled lab day (week 1) without wearing the required safety equipment, but, all students must obtain and wear the appropriate safety equipment by day 2 of lab (week 1

alpha hemolysis

The appearnce of a greenish color with bacterial growth on blood agar