Aseptic techniques (AQA GCSE Biology): Flashcards

Methods to prevent contamination when working with bacteria

Destroying all microorganisms to prevent contamination

Gamma radiation at factory

Autoclave - hot steam under high pressure

Bunsen burner flame until glowing red

One bacterial cell splits into two identical cells

Every 20 minutes

Introduces bacteria from breath

25°C

Reduces risk of harmful bacteria preferring body temperature

Kill microorganisms or stop their growth

Sterilise wire loop between cultures

Start number × $2^{\text{divisions}}$

Prevent dangerous anaerobic bacteria growing

Upside down near flame