Investigating Microorganisms Flashcards

All 6 cards in this deck

What is aseptic technique?

A set of precautions used when culturing microorganisms to stop unwanted microorganisms contaminating the culture (and to stop microbes escaping).

What is an autoclave used for when culturing microorganisms?

Sterilising growth medium and petri dishes with steam at high temperature and pressure, killing any unwanted microorganisms.

Why is an inoculating loop passed through a Bunsen flame before transferring microorganisms?

To sterilise it, killing any microorganisms on it so the culture is not contaminated.

Why is inoculation carried out close to a lit Bunsen burner?

The hot air rises and carries airborne microorganisms upwards, away from the plate, reducing contamination.

Why must petri dishes and culture vials be kept covered?

To stop microorganisms from the air contaminating the culture, and to stop the cultured microorganisms escaping.

True or false? A petri dish should be sealed all the way round the lid with tape.

False. Tape it in a few places only, so oxygen can enter and harmful anaerobic bacteria are not encouraged to grow.