成人论坛

Treating, curing and preventing disease - OCR Gateway Bacterial growth in cultures

Pathogens are everywhere. The body has evolved defences that act to prevent pathogens entering it. If a pathogen does enter the body then the immune system helps to fight it off.

Part of Biology (Single Science)Global challenges

Bacterial growth in cultures

Bacterial growth

can replicate approximately every 20 minutes by , which is a simple form of . This level of replication will depend on the availability of nutrients and other suitable conditions, such as temperature.

Diagram of how quickly bacteria can replicate within an hour

There are many ways to culture bacteria, and these include:

  • nutrient broth solution
  • colonies on an agar plate

Nutrient broth solution or culture medium, allows a liquid or gel to provide all the nutrients needed for bacteria to grow successfully. These must include:

  • carbohydrates for energy
  • nitrogen for
  • other minerals for growth and survival

are created by pouring hot molten mixed with nutrients into sterile , which are then allowed to set. Bacteria can be spread onto the plates, and allowed to form individual of the specific bacterium.

Uncontaminated cultures

If a specific bacterium is going to be or grown, other contaminating bacteria would compete for nutrients in the broth or agar. Plus some bacteria could be harmful and would complicate the results of experiments when testing the efficiency of antibiotics or other anti-microbial compounds.