super.sobs
Posts: 4
Joined: Tue Aug 28, 2007 10:13 am

### Please tell me the percentage of DNA in various fruits

the fruits i am concerned about are mango,apple,pear,grapes and one more(of you choice!) please i need to know as soon as possible,before the 2nd of September.PLEase!!
Sobs

MelissaB
Moderator
Posts: 1055
Joined: Mon Oct 16, 2006 11:47 am
Hi,

I'm confused about what you're asking. Are you asking for a percentage of weight or volume, and do you want to know dry weight/volume or wet weight/volume? Are you talking about the entire fruit trees/plants, or just the fruit? Can you tell us more about your project so we can help you better?

Also, is this supposed to be a survey (i.e. we tell you what we think the percentages are), or are you looking for the actual answers? If it's the latter, your time will be better spent on a search engine like google...although I'm not 100% certain that anyone actually has those data although you might be able to estimate them from other data.

super.sobs
Posts: 4
Joined: Tue Aug 28, 2007 10:13 am
actually we need to know the percentage by weight of DNA in a single fruit body,and not just an estimate but an accurate figure.i tried google but i can't find the answer to my question anywhere.but i m not that good at searching stuff(it's not quite a walk in the park as it's considered to be).can you help me,soon?
Sobs

MelissaB
Moderator
Posts: 1055
Joined: Mon Oct 16, 2006 11:47 am
Unfortunately, I don't think I can help because I don't think that anyone actually knows the answer. The molecular weight of DNA is approximately 500 daltons per base pair, so if you know how long each chromosome is you could calculate the weight of DNA in a single cell. Then if you know approximately how many cells are in the fruit, you can multiply the two to get the total weight of DNA in the fruit (and then divide that by the average weight of the fruit).

Trouble is, I can't find any information on either how many base pairs are in the chromosomes of these various fruits or how many cells are in each of these fruits. My guess is that in most if not all cases, no one has actually measured these parameters.

super.sobs
Posts: 4
Joined: Tue Aug 28, 2007 10:13 am
my project is: DNA Extraction and its Percentage in Various Fruits

Now what do i do?is there a general guess about DNA weight per fruit body or something like that?If actual figures are not available,those will do.what do you think?
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geoffbruton
Former Expert
Posts: 123
Joined: Mon Aug 29, 2005 10:02 am
Try typing your actual project title into Google, or another search engine. I just did and found a lot of useful information; in particular, on how to extract DNA from fruit...

Quantifying the amount extracted may require some more thought.

Please research the sites and let us know your thoughts and any specific questions you may have.

Good luck!
Geoff.
Geoff Bruton
Firearm & Toolmark Section
Ventura County Sheriff's Department
Forensic Sciences Laboratory

super.sobs
Posts: 4
Joined: Tue Aug 28, 2007 10:13 am
sadly,the final date has come and i am leaving tomorrow to another city where the exhibition is being held.i had found the procedure of extracting DNA from fruits(i got the idea from internet in the first place) but couldn't find its quantity in the fruits.i want to thank everyone for their help and support.Thank you and pray for the exhibition. i am going to guess the quantities,if i am lucky,no one would know...
Sobs

Louise
Former Expert
Posts: 921
Joined: Mon Jan 16, 2006 2:17 pm
super.sobs wrote: i am going to guess the quantities,if i am lucky,no one would know...

Wow. Don't do that. Better to say you don't know then to lie. If you get caught committing this type of fraud, the consequences could be very serious for you and your grade.

Louise

MelissaB
Moderator
Posts: 1055
Joined: Mon Oct 16, 2006 11:47 am
Louise is right. The judges are very likely to know that we don't know the weight of DNA in various fruits, and they will then know that you have made up the data. If you don't know, say you don't know.