Media & Culture

Question 1

What are the requirements for Microbes to be grown

Answer 1

• Physical requirements
• Temperature
• pH
• Osmotic pressure - can cause the cell to explode or shrivel up
  
  • Chemical requirements
• Carbon
• Nitrogen,
• sulfur, and phosphorous Trace elements

Question 2

Why do microbes need Nitrogen?

Answer 2

To synthesis ammino acids and proteins

Question 3

How is media made?

Answer 3

Nutrient rish power is mixed with water.

This mixture is then put in a bottle and autoclaved - inreasing temp and pressure to kill any microbses

Question 4

What are the 4 different types of medium?

Answer 4

Basic

Nutrient / Enriched medium

Selective Medium - can prevent certain bacteri from growing but allow others

Differencial Medium - indicators can be added to the medium to allow for visual differences.

Question 5

What are the two different methods of culturing microbes

Answer 5

Liquid Culture - can be grown in liquid medium in a test tube

Culture plates - traditional petri dishes with solidified medium.

Question 6

What is put into the medium to solidify it?

Answer 6

Agar (Agrose)

Question 7

Name the 3 specilasied medium meantioned in the power point?

Answer 7

McConkey’s Agar Plates

Mannitol Salt Agar Plates

Blood Agar Plates

Question 8

Is McConkeys Basic, Enriched, Differencial or Selective?

Answer 8

Differencial - Will turn the conlenies pink when they are lactose consuming bacteria

Selective - It will only grow Gram Negative bacteria.

Question 9

Is Mannatol Salt Agar, Basic, Enrished, Selective or Differential?

Answer 9

It is Selective and Differential.

Selective as it only grows bacteria that like high salt content

Differencial cause it changes colour if Mannatol fermenting baceria is present.

Question 10

Is Blood Agar, Basic, Enriched, Selective or Differencial?

Answer 10

It is Enriched and Differencial.

Enriched by 5% Sheeps blood.