Pulvinus
A pulvinus (pl. pulvini) is a joint-like thickening at the base of a plant leaf or leaflet that facilitates growth-independent (nyctinastic and thigmonastic) movement. Pulvini are common in members of the bean family Fabaceae (Leguminosae) and the prayer plant family Marantaceae.
Pulvini may be present at the base or apex of the petiole (botany) or where the leaflets of a compound leaf are inserted into the rachis. They consist of a core of vascular tissue within a flexible, bulky cylinder of thin-walled parenchyma cells. A pulvinus is also sometimes called a geniculum.
Pulvinar movement is caused by changes in turgor pressure leading to a contraction or expansion of the parenchyma tissue. The response is initiated when sucrose is unloaded from the phloem into the apoplast. The increased sugar concentration in the apoplast decreases the water potential and triggers the efflux of potassium ions from the surrounding cells. This is followed by an efflux of water, resulting in a sudden change of turgor pressure in the cells of the pulvinus. The process is similar to the mechanism of stomatal closure.
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by The Raconteurs
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by Raconteurs
Blue Veins
by: The RaconteursWhen I was surrounded by the world
You were the only one who came
And you were the only one astounded
Which kept me grounded
As the other girls thrashed my very name
Then I looked over
Just in time to see her smiling back at me
And saying everything's OK
As long as you're inside my blue veins
Your blue veins
Yeah and the feeling that you gave me
No matter what I do or where I go
It always will remain
And those who would enslave me to get to me must get past you and will have no luck
Cause you'll protect me from all pain
The most beautiful, yeah the most beautiful thing cause anything else can't compare
Must be the blood that's running through your blue veins
Your blue veins
[Strange part in reverse]
Your blue veins
And I know you won't deceive me
Like the rest and there's nothing you need to explain
You always were the first one to believe me
When I said to you girl
I think it's gonna rain
But I could be wrong
Yeah but all of these things
All these things
They're all truly nice but ain't nothing
Ain't nothing compared to the love that's running through your little blue veins
Your blue veins