"Chris" wrote in message
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On Sep 16, 6:57 pm, "symplastless" wrote:
"Chris" wrote in message

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On Sep 14, 7:40 pm, "symplastless" wrote:

Thank you for your input.

Chris show me one per. table that identifies elements as nutrients.

--
Sincerely,
John A. Keslick, Jr.
Consulting Tree Biologistwww.treedictionary.com
andhttp://home.ccil.org/~treeman
Watch out for so-called tree experts who do not understand tree biology.
Storms, fires, floods, earthquakes, tornado's, volcanic eruptions and
other
abiotic forces keep reminding humans that they are not the boss.

The table I mentioned above (the one in Campbell & Reece) has is
titled "Plant Nutrients" and it has two columns. The first is divided
into two subsections, titled macronutrients and micronutrients.
Nitrogen, for example, is listed as a macronutrient. The second column
is titled, "Form available to plants." When we look there, we see the
(macro)nutrient nitrogen is available not as N or even N2, but only as
NO3- or NH4+. So the plants cannot absorb elemental nitrogen (the
common atmospheric form of which is N2) but they must get their
nitrogen as either nitrate or ammonia.

Note the difference between humans and plants here. Human nutrients
are commonly listed (and I have taught nutrition as well as General
Biology) as energy, protein, carbohydrate, lipid, water, minerals, &
vitamins. Plants do not need the more complex forms of these
substances, and require particular elements- but those elements must
be in particular forms to be absorbed. Humans need minerals (that
contain particular elements) and we need to have them in a particular
form to be USED, not just absorbed. Granted, there's some leeway in
that. But not all that much. We cannot digest large chunks of CaCO3,
nor do we absorb it very well, so if you're taking calcium
supplements, you much better off taking calcium citrate than calcium
carbonate- and for humans, calcium is indeed a macronutrient.

That just proves the point that the books are wrong. They way it is being
taught is wrong and confusing.

Define element

define nutrient

define food


--
Sincerely,
John A. Keslick, Jr.
Consulting Tree Biologist
www.treedictionary.com
and
http://home.ccil.org/~treeman
Watch out for so-called tree experts who do not understand tree biology.
Storms, fires, floods, earthquakes, tornado's, volcanic eruptions and other
abiotic forces keep reminding humans that they are not the boss.


Chris