How to Measure Bacterial Growth
Gather your materials., Use your pour plate or spread plate., Make sure you have the concentration right., Count the bacteria.
Step-by-Step Guide
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Step 1: Gather your materials.
There are a few special tools you should have in addition what is stocked in most biology labs.
Having your instruments and containers ahead of time will allow you to complete the experiment without having to run back and forth to the cabinet.
It is important to know what each piece will be used for up front.
You should know some basic terms as well.
Get a counting chamber.
These tools have a chamber, slide, and microscope built in, so they are easy to set up and use.
You can buy them from lab and classroom supply companies.
They come with instructions that guide you through the whole process.
Get a pour plate or a spread plate.
These are the containers you will observe the bacteria in.
Culture is the term used to describe an organism grown artificially for an experiment.
Broth is a liquid medium that the culture grows in. -
Step 2: Use your pour plate or spread plate.
You can also place the bacteria directly onto a plate for viewing under a microscope.
Apply the culture to the plate and place under a microscope.
Observe how many bacteria cells there are., If there are too many bacteria, they will overlap and you won’t get an accurate count.
Dilute the culture by mixing it with more broth.
If there are too few, you won’t have enough for an accurate number.
Filter out the broth using a filtration system. , The last step is physically counting them.
Look through the magnifier on the counting chamber and write down how many you see.
Compare this with other tests. -
Step 3: Make sure you have the concentration right.
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Step 4: Count the bacteria.
Detailed Guide
There are a few special tools you should have in addition what is stocked in most biology labs.
Having your instruments and containers ahead of time will allow you to complete the experiment without having to run back and forth to the cabinet.
It is important to know what each piece will be used for up front.
You should know some basic terms as well.
Get a counting chamber.
These tools have a chamber, slide, and microscope built in, so they are easy to set up and use.
You can buy them from lab and classroom supply companies.
They come with instructions that guide you through the whole process.
Get a pour plate or a spread plate.
These are the containers you will observe the bacteria in.
Culture is the term used to describe an organism grown artificially for an experiment.
Broth is a liquid medium that the culture grows in.
You can also place the bacteria directly onto a plate for viewing under a microscope.
Apply the culture to the plate and place under a microscope.
Observe how many bacteria cells there are., If there are too many bacteria, they will overlap and you won’t get an accurate count.
Dilute the culture by mixing it with more broth.
If there are too few, you won’t have enough for an accurate number.
Filter out the broth using a filtration system. , The last step is physically counting them.
Look through the magnifier on the counting chamber and write down how many you see.
Compare this with other tests.
About the Author
Claire Cruz
Brings years of experience writing about creative arts and related subjects.
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