How to grow bacteria?

Question

We have this science experiment on how to grow a bacteria, our teacher told us to use gelatin, beef stock, and sugar as an alternative for agar. I am confused on why we need gelatin, beef stock, and sugar in growing a bacteria. What ingredient is in those 3 materials that can aid in growing bacteria?

score 5 · Answer 1 · edited Sep 04 '18 at 14:52

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There are several requirements for bacteria to grow.

A carbon source - Sugar
A nitrogen / amino acids source - Beef stock
Gelatin is there to hold everything in place, it doesn't provide any nutrients.

edited Sep 04 '18 at 14:52

iayork

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answered Sep 02 '18 at 12:13

prab4th

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The list is incomplete. – Sep 02 '18 at 21:33

anon · Answer 2 · 2018-09-02T21:39:41.040

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Everything that lives needs food to grow. That food may be as simple as nutrients needed to build parts to more complex tasks like storing and/or converting energy.

Different bacteria require different things. A nutrient source like beef stock contains lots of amino acids and proteins which can feed a large spectrum of bacteria.

Sugar is a densely packed energy store that many bacteria can use for powering biologic processes.

Gelatin is a mixture of peptides and proteins which adds even more nutrients to the system. More importantly, its thick gelatinous structure acts as a binding agent/ substrate which keeps everything from sloshing around in the dish (which can be very inconvenient when moving it around).

In short the simple petri dish is about providing a wide variety of nutrients so that it can support the growth of a wide variety of microbes.

edited Sep 02 '18 at 21:39

answered Sep 02 '18 at 17:52

anon

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"Converting" rather than "producing" energy. – Sep 02 '18 at 21:35
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You know you could just edit it for a point that small – anon Sep 02 '18 at 21:39
i only edit my own answers. – Sep 03 '18 at 05:53

How to grow bacteria?

2 Answers2