Reef Chemistry Question of the Day #82 Heavy Elements

[Randy Holmes-Farley]

Reef Chemistry Question of the Day #82

Which of the following is the heaviest element known to be used (in a positive way) in any living organism? Which is the heaviest used in organisms larger than bacteria?

A. Iron
B. Mercury
C. Tungsten
D. Iodine
E. Zinc
F. Bismuth

Good luck!




























.

 

[cope413]

I guess E. Zinc

 

[H2O]

A . Iron

 

[beaslbob]

doesn't it depend on how much of the element you use?

 

[beaslbob]

I say b mercury

 

[Randy Holmes-Farley]

doesn't it depend on how much of the element you use?

The question doesn't involve people. Just what elements organisms use.

 

[Mark...]

I have to say iron since its needed for hemoglobin.

 

[lionfish5740]

That's the kind of question I had in my chem class... Not likely to guess it correctly!

 

[labas39]

Bismuth

 

[redfishbluefish]

Well, Mercury and Bismuth are OUT.......although we do suck down a slug of bismuth everytime we want to settle that upset stomach (Peptobismol), but has no biological significance. And forget mercury...a nasty little poison.


And I think we all know about Iron and Iodine both important to us (humans) with blood and the thyroid, respectively, (and other proteins/enzymes), so both these guys are IN.


And finally Tungsten and Zinc are also found is proteins/enzymes, so they are both IN.


Without looking up a periodic table, I believe Tungsten is the heaviest of the IN's and is my choice for both queries....found in proteins/enzymes of living stuff.

 

[beaslbob]

the human element

 

[Randy Holmes-Farley]

And the answer is....

Tungsten for bacteria
Iodine for higher organisms

redfishbluefish was oh so close...

In order of decreasing mw, the metals are:

Bismuth
Mercury
Tungsten
Iodine
Zinc
Iron

So if we start working our way down from the top...

Bismuth has no known natural biological utility (but is the main ingredient in Pepto Bismol)
Mercury has no known biological utility
Tungsten is used in some enzymes in bacteria but not higher organisms.
Iodine is used in many organisms, including people (although it is not known to be needed by most corals)
Zinc and iron are widely used by organisms.