Comments for How Plants Work

Comment on Plant Mythbusters (#1) – Seeds From Ancient Egyptian Tombs That Germinate by plantguy

plantguy — Wed, 22 Feb 2012 03:15:04 +0000

Hey Charlie,
Thanks for the heads up.
I read the paper in PNAS online (http://www.pnas.org/content/early/2012/02/17/1118386109.abstract).
They indeed regenerated an ancient plant (32,000 years old), but not through seed germination.
They cloned (in vitro) living cells from floral ovary tissue and then regenerated whole plants using well-known plant tissue culture techniques. These plants then grew, flowered and set viable seed.
Even though they weren’t able to germinate viable seeds from these frozen, ancient plants, this is still very, very “cool”.

Thanks for your comment!

Comment on Plant Mythbusters (#1) – Seeds From Ancient Egyptian Tombs That Germinate by Charlie Sohl

Charlie Sohl — Tue, 21 Feb 2012 23:41:03 +0000

but see this recent story http://news.sky.com/home/strange-news/article/16174136

Charlie

Comment on Plants That “Remember” – Some Plants Can Record Environmental Experiences For Future Reference By Altering Their DNA by plantguy

plantguy — Sat, 18 Feb 2012 04:15:00 +0000

Hi Joe,
That’s an interesting idea, but it appears that most plants need an extended (weeks to months) period of “cold” treatment before they are “vernalized”. This required period of “cold” and the effective temperatures also depends on the plant species in question.

Many plants, however, can be induced to be a bit more cold hardy (or “cold-hardened”) by several days of near-freezing temps. But this is mainly due to somewhat transient metabolic and physiological shifts that occur in the plant in response to the cooler temperatures.

Comment on Plants That “Remember” – Some Plants Can Record Environmental Experiences For Future Reference By Altering Their DNA by joe

joe — Thu, 16 Feb 2012 22:15:29 +0000

Is it possible then to force the plants to think they’ve been through winter, such as making them go through 1 or 2 frosts, so that the plants don’t have to go through an entire winter?

For example, raising the seeds indoors or in a greenhouse during part of winter, and then planting them out near the end, in places where the winter would be too harsh for them.

Comment on Does the Moon Affect Plants? Part 2: Moonlight and Biorhythms by plantguy

plantguy — Fri, 30 Dec 2011 15:00:07 +0000

Hi Mevlut,
What research are you doing?

Comment on Does the Moon Affect Plants? Part 2: Moonlight and Biorhythms by mevlut

mevlut — Fri, 30 Dec 2011 09:25:42 +0000

hı;
ı’m mevlut.ı’m universty student in Turkey.
ı research about the effect of moonlight on trees.
can you help me ?
thanks

Comment on How Plants Survive The Cold (Or Not) by plantguy

plantguy — Mon, 14 Nov 2011 05:19:45 +0000

Freezer.

Comment on How Plants Survive The Cold (Or Not) by ck

ck — Mon, 14 Nov 2011 03:18:12 +0000

so im doing this science project which is which plant would die quicker in a freezer or a cabnet pls help me

Comment on Plants Don’t Convert CO2 into O2 by Audrey

Audrey — Fri, 04 Nov 2011 06:22:52 +0000

This was really helpful! Just wanted to say thanks!

Comment on Plants Don’t Convert CO2 into O2 by plantguy

plantguy — Mon, 03 Oct 2011 14:24:46 +0000

Rodigo,

Take a deep breath.
Now you’ve just demonstrated where some of those extra oxygen (O2) molecules go. From the chloroplasts, into the plant cells, out of the cells, out of the leaves through the stomates, and ultimately into the atmosphere.
The three O2 molecules you’re concerned about (produced in the so-called “light reactions”) are not involved in any way with the CO2-fixation reactions (Calvin cycle).
Hoped this answered your question.

P.S. If you are concerned about the accounting for the oxygen in the Calvin Cycle, this is more complicated due to the complexity of this metabolic pathway. A simple summary of the Calvin Cycle is:

3 CO2 + 9 ATP + 6 NADPH –> glyceraldehyde-3-phosphate (C3H6O6P) + 9 ADP + 8 Pi + 6 NADP+

The high-energy compounds ATP and NADPH are generated during the “light reactions”. The glyceraldehyde-3-phosphate (PGA) is the main stable product of carbon fixation during the Calvin cycle. Subsequent metabolic reactions covert 2 PGAs into glucose + two phosphates (2 PO3). The “extra” oxygens in this case wind up in the phosphates.

Yes, it’s complicated. That’s why it was so difficult to figure out in the 1940′s and 1950′s. And why Calvin (along with two other colleagues) received the Nobel prize.