[TML] Alien ecologies

[Bruce Johnson]

On Aug 29, 2008, at 1:59 PM, Greg Kettler wrote:

> On Fri, Aug 29, 2008 at 3:56 PM, Bruce Johnson
> <johnson at pharmacy.arizona.edu> wrote:
>
>>>
>>> Remember that the height of the solar spectrum has been squished by
>>> a factor
>>> of 10.55, so differences are way more then this makes clear.  Note
>>> the the
>>> blue peak of chlorophyll a (the most common form, considered
>>> "universal") is
>>> well down from the peak of sunlight, by about 30-38%.
>>
>> That's because the absorbtion peak does not depend on the protein
>> (which can change via evolution) but the captive metal atoms  
>> chemistry
>> (which cannot)
>
> The peak can and does change. Chlorophyll b has a different peak, but
> the same metal ion.



-- 
Bruce Johnson
University of Arizona
College of Pharmacy
Information Technology Group

Institutions do not have opinions, merely customs