Counting Rhos

September 17, 2012 5:34 PM

Do you like biology? Do you like numbers? Like, actual numbers and not the television show? Take a look at BioNumbers.

Feel overwhelmed? Don't know what to look for? Start with Amazing BioNumbers and work your way up to the BioNumber of the month, which goes into a bit more depth about the science behind the counting.

posted by Blazecock Pileon (10 comments total)

Says there the genome of the amoeba is waaay bigger than the genome of a person. Like, stupid bigger.

I can't say to the contrary. But that don't sit right with me.
posted by Egg Shen at 5:42 PM on September 17, 2012 [1 favorite]

Ace title too, btw.
posted by Egg Shen at 5:44 PM on September 17, 2012

If that makes you feel bad, don't compare chromosome count with this fern.
posted by benito.strauss at 5:46 PM on September 17, 2012

Great resource!

But it doesn't really help us figure out the capacity of a rhino's bladder.
posted by Kabanos at 6:02 PM on September 17, 2012

Number of skin cells: Dividing number of bacteria on the skin (10^12 BNID 105712) by this value gives a ratio of ~10 'skin' bacteria to one skin cell.
posted by not_on_display at 6:38 PM on September 17, 2012

Hundreds--thousands of atoms per protein, and the average radius of a folded protein is on the scale of nanometers. What...

Thanks for posting.

(Somewhat related, the Physics Hypertextbook, which I kept on my homepage during freshman mechanics. Fun stuff.)
posted by miniraptor at 7:51 PM on September 17, 2012 [1 favorite]

Says there the genome of the amoeba is waaay bigger than the genome of a person.

There is no solid relationship between the complexity of an organism and the size of its genome. After all, how does one even define complexity? Size? Number of cells? Capacity to respond to its environment? (and then how would you quantify something like that?) What seems like an intuitive notion on its surface breaks down rather quickly when you start to look at the details.

Even if you take for granted the fact that a dolphin is more complex than a slime mold, you can't assume that difference will be reflected in the size of their respective genomes. Genes vary in size (the correlation between number of genes and number of total base pairs in an organism is fairly loose), and genes are not all necessarily functional or useful.

But what really makes things interesting are the higher-level processes like gene regulation, wherein one gene can control the expression of many others—and other genes can regulate the regulatory genes, and two genes can counter-regulate each other, etc, etc. Suddenly, the system becomes explosively nonlinear; it's no longer simply the sum of its parts. Once you've added that layer of complexity, what matters is no longer the number of individual instructions, but how effectively they interact.
posted by dephlogisticated at 8:59 PM on September 17, 2012 [4 favorites]

So maybe the coding regions of the amoeba genome are identical to ours except for all the extra repressors in their junk DNA.
posted by waving at 4:10 AM on September 18, 2012

Now THIS is NumberWang!
posted by Saxon Kane at 9:32 AM on September 19, 2012

Interesting idea but doesn't seem comprehensive enough. I work in the olfactory system. So I tried "size of olfactory granule cell", then "olfactory granule cell", "olfactory bulb" etc. all with no results.
posted by peacheater at 11:46 AM on September 19, 2012