Mac, TSI, Motility

What is the pH indicator found in MaConkey agar?

• Cresol red

• Neutral red

• Phenol red

• Bromothymol blue

What are the chemical inhibitors found in MacConkey agar?

• Urea and Safranin

• Neutral red and Phenol red

• Bile salts and Crystal violet

• Ferric ions and Yeast

What is the carbohydrate (sugar) found in MacConkey agar?

• Glucose

• Lactose

• Sucrose

• Mannitol

What organisms does MacConkey agar inhibit?

• Lactose fermenters

• Proteus species

• Gram (-) bacteria

• Gram (+) bacteria

A medium that allows some organisms to grow, and inhibits the growth of others is called:

• Enteric

• Differential

• Selective

• Differential and Selective

What kind of medium distinguishes one type of organism from another?

• Selective

• Differential

• Selective and Differential

• Simple

What end product is produced when H₂S reacts with ferric ions in the TSI test?

• Acid end product

• Alkaline end product

• Ferrous sulfide

• Hydrogen sulfide

What gas may be produced in the TSI test that causes a black precipitate to form?

• Hydrogen sulfide gas

• Ferrous sulfide gas

• Carbon dioxide gas

• Nitrogen gas

What is the pH indicator in TSI?

• Cresol red

• Phenol red

• Neutral red

• Bromothymol blue

Interpret the TSI test shown

• Alk/H₂S

• Alk/A, H₂S

• A/H₂S

• A/Alk, gas

Tags

NGSS.HS-PS1-2

NGSS.HS-PS1-4