sav101
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Joined: Thu Oct 11, 2018 6:30 pm
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Growing Chlorella

Postby sav101 » Thu Oct 11, 2018 6:36 pm

I’m working on a science fair project where I am testing the affect of Paraben son Chlorella algae. The only problem I’m having during my research is on getting accurate and clear information on how to measure the growth of the Chlorella algae. I’ve come across multiple sites but the information just isn’t very clear, therefore my question is how can the growth of Chlorella be measured?

SciB
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Joined: Fri Feb 01, 2013 7:00 am
Occupation: Retired molecular biologist, university researcher and teacher

Re: Growing Chlorella

Postby SciB » Thu Oct 11, 2018 7:57 pm

Hi and welcome to Scibuddies

Chlorella is a single-celled green alga that grows easily and has some remarkable properties that make it a favorite for experiments and research. Your question of how to measure growth of the algae comes up a lot and what I tell students first is that it depends on how accurately you want to measure it.

You can look at two cultures of chlorella and see that one is darker and denser because it has more algal cells, but that is not a quantitative measurement--it does not give you a number value for the growth so you can accurately compare one chlorella culture with another.

One fairly accurate way to measure the growth is by taking equal volumes of each culture, filtering them to collect the cells and then weighing them. Cultures that have grown the most will have the most cells per unit volume and will weigh more.
Carolina Biological Supply Co. sells filter paper for lab use: https://www.carolina.com/lab-supplies-a ... lter_paper
You will also need a fairly accurate digital scale that weighs in grams, but these are not too expensive and they are useful in the kitchen and for future science projects.

The most accurate and easiest way to measure growth is to use a spectrometer or nephelometer, but these would be too expensive for you to buy. If your school has one then you can use it to and what you are measuring is the light absorbance of the culture. The more algal cells in the culture, the more light it will absorb.

Let me know if you have more questions. I hope this helps!

Sybee

sav101
Posts: 2
Joined: Thu Oct 11, 2018 6:30 pm
Occupation: Student

Re: Growing Chlorella

Postby sav101 » Thu Oct 11, 2018 8:25 pm

Thank you so much for the helpful information!

SciB
Expert
Posts: 1673
Joined: Fri Feb 01, 2013 7:00 am
Occupation: Retired molecular biologist, university researcher and teacher

Re: Growing Chlorella

Postby SciB » Fri Oct 12, 2018 1:06 pm

You are most welcome!

If you need more details about measuring chlorella growth, post again and I will help you. If you aren't sure of something, it is better to ask a question. One wrong experiment can ruin a whole science project.

Good luck!

Sybee


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