Velamen
Velamen is a spongy, multiple epidermis that covers the roots of some epiphytic or semi-epiphytic plants, such as orchid and Clivia species.
The velamen of an orchid is the white or gray covering of aerial roots (when dry, and usually more green when wet as a result of the appearance of underlying photosynthetic structures). It is many cell layers thick and capable of absorbing atmospheric moisture and nutrients, but its main function may lie in protecting the underlying cells against damaging UV rays (Chomicki et al., 2015). Often, the roots of orchids are associated with symbiotic fungi or bacteria; the latter may fix nutrients from the air. This functionality allows the orchid to exist in locations that provide a reproductive or vegetative advantage such as improved exposure or reduced competition from other plant species.
The velamen also serves a mechanical function, protecting the vascular tissues in the root cortex, shielding the root from transpirational water loss, and, in many cases, adhering the plant to the substrate.
Podcasts:
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by Willamena
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by Willy Moon
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by Willy Moon
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by Willy Moon
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by Willy Moon
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by Willy Moon
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by Willy Moon
The Things That I Forgot
by: WillamenaWell I don’t like taking pictures
‘cause I don’t like to admit
That someday I’ll be older
And there’ll be times that I forget
So I don’t keep a scrapbook
‘cause I don’t need that weight
Well the memories are like ghosts
And they haunt me when it’s late
Give me back those simple days
Back when we used to dream
And I dream for more than I have
I want more than I got
But I believe in the simple things
Yeah the things that I forgot
But I got a couple pictures
Because sometimes I like to see
How I looked when I was younger
‘cause I didn’t look that way to me
And my daddy he kept a scrapbook
And I’d leaf through once in a while
Those old black and white pictures
Of wedding cakes and sisters
Yeah, they make me smile
Give me back those simple days
Back when we used to dream
And I dream for more than I have
I want more than I got
And I believe in the simple things
Yeah the things that I forgot, yeah
Give me back those simple days
Back when we used to dream
And I dream for more than I have
I want more than I got
And I believe in the simple things
Yeah the things that I forgot
Well the things that I forgot