Microbiology Quiz #1 Cedarville University Dr. Collins

True or false: the aseptic technique is free of contamination

true

According to aseptic technique, what should be done before each lab?

Sterilize lab bench and turn on flame

According to the aseptic technique, what should one work around?

Zone of asepsis

What is the common goal for those working with the aseptic technique?

use common sense

What is necessary in order to characterize and study a specific type of species?

Pure culture

What are the three way in which isolated colonies can be obtained?

Streak plate, spread plate, and pour-plate method

In which isolation method is bacteria from a culture transferred to a plate using an inoculating loop?

streak-plate method

How are the bacteria spread with a streak plate?

In a pattern

Which isolation method uses spreading a dilute bacterial culture across an agar plate using a sterile hockey stick?

Spread-plate method

Which isolation method yields isolated colonies when a small volume of a dilute bacterial culture is added to a sterile dish with melted sugar?

Pour-plate method

What is the general meaning of asepsis?

free of contamination

What is movement through a semi-solid surface via the rotation of flagella?

Swarming Motility

What is movement along a solid surface via the extension and retraction of pili?

Twitch motility

What did the P.A. swarm motility look like?

Big blob with dot in middle

What did the P.A. Twitch look like?

Circle with dot in middle

What did the S.A. swarm look like?

Two dots with line connecting them

What did the S.A. twitch look like?

Dot with a small funny lining on one side

Which type of cells have a thick layer of peptidoglycan in their cell wall?

Gram positive

Which type of cells have a thinner layer of peptidoglycan and a LPS layer in their cell wall?

Gram Negative

Which type of cell stains purple?

Gram positive

Which type of cell stains pink?

Gram negative

What are the lipids contained in acid-fast cells?

mycolic acids

What type of cell stains red?

Acid-fast

What type of cell stains blue?

Non-acid-fast

What are the characteristics of a proper smear?

Bacteria are evenly spread on a slide (completely)-separated from one another

Bacteria are not washed off the slide

Bacteria form is not distorted (heat can distort it)

What is the primary gram stain?

crystal violet

What is the secondary gram stain?

Safranin

What is the importance of the iodine in the gram staining process?

allows for interaction between dye and cell wall

What is the primary stain for acid-fast cells?

carbolfuchsin

What is the secondary stain for acid-fast cells?

methylene

What is the method where bacterial is serially diluted and plated onto growth media?

Standard Plate Count

What does it mean for a plate to have too few to count (TFTC)

Plate contains less than 30 colonies

What does it mean for a plate to have too numerous to count?

Plate has more than 300 colonies

Which method for bacterial growth is considered the direct method of quantification?

standard plate count

How can bacterial populations be measured indirectly?

Measuring the turbidity

What is the name of the instrument for measuring turbidity?

Spectrophotometer