Ok, I see. Thanks a lot for your help, I really appreciate it. 

I was asking because in my manual I have to fill this table and I don`t know what information I have to put. If you notice the part of E.coli, there is specific information,  that´s what I´m looking for but I can´t find it. Do you know how can I search it or find the answer? 

Ok, thank you again. Have a nice week :)

@ Ali,

CHO should be the Chinese hamster ovary (CHO).

GHO cells are an epithelial cell line derived from the ovary of the Chinese hamster, often used in biological and medical research and commercially in the production of therapeutic proteins

@ Michel,

Please see some examples of the rRNA sizes (Kb) of different species at link below:

[https://www.thermofisher.com/us/en/home/references/ambion-tech-support/rna-isolation/general-articles/ribosomal-rna-sizes.html]

Human: 18S, 28S

Mouse: 18S, 28S

Xenopus: 18S, 28S

Drosophila: 18S, 28S

Tobacco Leaf: 16S, 18S, 23S and 25S

Yeast: 18S, 26S

E. coli: 16S, 23S

@Yuan-Yeu Yau 

Thank you for your help, It´s so useful. You give me another idea to find the answer to my question. When I finally find it I will give you the answer, in order to complement our knowledge. 

Thanks a lot.

Like human and mouse, Chinese hamster is a mammal. So, I think they should also have the rRNA with 18S and 28S.

Attached Figure shows tobacco rRNA on a gel. From: Zymo Research

The legend of the Figure:

"Isolation of total RNA from 10 mg of a fresh leaf material (Nicotiana sp.) using the ZR Plant RNA MiniPrep™. Leaves were minced then processed using a FastPrep®-24 instrument (MP Biomedicals). Samples 1 and 2 were loaded in 2x and 1x volume aliquots, respectively, and resolved in a 1% (w/v) nondenaturing agarose gel. RNA Millenium™ Markers (Ambion) were used as size standards."

http://www.zymoresearch.com/rna/total-rna-purification/soil-fecal-plant-rna/zr-plant-rna-miniprep

@ Ali,

For a rookie or a beginner sometimes it is hard for them to find a way to get started for a question (because they have no experimental experience at all). For giving them a few detail answers will help them in figuring out how to approach this kind of question later (and we ourselves also learn from doing this, too). For example, one of the answers provided above can give them an idea that the rRNA patterns on a gel can be different from different organisms. Also the gels used to run can be 'denatured' or 'non-denatured', what does that mean. The attached Figures show some stuffs that are not asked in his lab notebook. And I believe they will go online to find more related stuff if they are interested..

Besides, those answers are not only for the person who post this questions, but also for others who are following or read this question.

But, thank you for your suggestion.

Hi Ali,

Thanks for your explaination. I understood. I also did my studies by searching printed journals in the libraries in absence of internet. I remember I used to stay in the small library room with only a few collections of important plant journals doing my required-paper searching.

The goal of providing an image is just to let them know that people have done that and how the 4 rRNA bands should look like on a gel to support my previous answers. Because providing only 'words' (ex. such as 25S, 23S, 18S and 16S) in my previous answer is just not good enough.

Of course, they might not be able to produce a high-standard picture like that (and we don't have any intention to ask the beginners to produce such high-standard gel picture like that), but they need to know the fact that 4 rRNA bands should be presented, not only 2 bands (for plants). What is the best way? I think the best way is to show them the data. The old saying goes: "Seeing is believing'.

Have a good day.