Lab Practical: MOTILITY

Question 1

True motility

Answer 1

Rotation of flagella

Question 2

Brownian movement

Answer 2

Motion due to collision with molecules of surrounding medium.

Not true motility

Question 3

Procedures in which MOTILITY may be determined

Answer 3

• Flagella Staining
• Semi-solid Media
• Hanging Drop Procedure

Question 4

Flagella Staining

Answer 4

• Special staining process leaves a precipitate around flagella so that they appear larger
• Amphitrichous or peritrichous

Question 5

Semi-Solid Media

Answer 5

• Inoculate motility medium by performing a stab
• Growth only along stab line = non-motile
• Growth spreading through medium - motile

Question 6

Hanging Drop Procedure

Answer 6

• Place small dab of petroleum jelly at each corner of cover slip
• Broth Culture: loopful of broth onto cover slip
• Plate Culture: 2 loopfuls of distilled water onto cover slip and stir in a sample of bacterial culture
• Place depression slide on top of cover slip.
• Concavity covers drop Invert slide so drop is hanging into the concavity
• Observe movement at 400x

Question 7

What type of slide was used in the Hanging Drop Procedure

Answer 7

Depression slide