Volvox- young colony

Images made through a microscope. All subject types.

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NikonUser
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Volvox- young colony

Post by NikonUser »

EDIT: title changed, was "Colonial Algae for ID"

A sphere (?) with individuals on the surface; a gelatinous matrix on the outer surface; looks like each cell has a single flagellum that pierces the gelatinous sheath.
Top half is focused at the diameter, bottom half focused at top of sphere (but these are single frames so this must be more of a disc than a sphere).
Individual cells, bottom image is actual pixels, are about 9µ wide.
Olympus BHS DIC, 40x SPlan Achro, 1.25x intermediate lens, 2.5x NFK relay lens.
Image
Image
NUM10120
Last edited by NikonUser on Thu Dec 09, 2010 12:26 pm, edited 1 time in total.
NU.
student of entomology
Quote – Holmes on ‘Entomology’
” I suppose you are an entomologist ? “
” Not quite so ambitious as that, sir. I should like to put my eyes on the individual entitled to that name.
No man can be truly called an entomologist,
sir; the subject is too vast for any single human intelligence to grasp.”
Oliver Wendell Holmes, Sr
The Poet at the Breakfast Table.

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Mitch640
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Post by Mitch640 »


NikonUser
Posts: 2693
Joined: Thu Sep 04, 2008 2:03 am
Location: southern New Brunswick, Canada

Post by NikonUser »

Mitch: The cells seem to be too tightly packed for it to be a Volvox sp.
Also, each Volvox cell has 2 flagellae, these guys seem to have just 1.
NU.
student of entomology
Quote – Holmes on ‘Entomology’
” I suppose you are an entomologist ? “
” Not quite so ambitious as that, sir. I should like to put my eyes on the individual entitled to that name.
No man can be truly called an entomologist,
sir; the subject is too vast for any single human intelligence to grasp.”
Oliver Wendell Holmes, Sr
The Poet at the Breakfast Table.

Nikon camera, lenses and objectives
Olympus microscope and objectives

Mitch640
Posts: 2137
Joined: Sun Aug 15, 2010 1:43 pm

Post by Mitch640 »

I thought maybe it would provide a lead to the real thing, as it looked so similar in so many parts. But yours, going by the middle image, looks like it might be disk shaped, a losenge, since so much of it is in focus, apart from the edge. A ball shape could not show that, without a stack.

BJ
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Joined: Sat Sep 29, 2007 10:53 am
Location: England

Post by BJ »

Hi,

I am pretty sure that this is indeed Volvox, but a recently released daughter colony which does not yet show the "typical" appearance. The cells in surface view are still tightly packed around the circumference of the colony and have yet to space themselves out. When cell division is completed, the colony increases in size by increase in cell size and increased cell separation.

Only one flagellum per cell..... I reckon the other one just fell off !! This is quite common in flagellates -usually in response to some stress eg temperature change or mechanical stress when sampling or subsampling.

In cells with two flagella, one of the two is more prone to fall off than the other. The flagellum can regrow over a period of an hour or two.

In Platymonas, a marine green flagellate with 4 flagella, i find cells with zero, 1, 2, 3 or 4 attached flagella... with 4 being the least common...but perhaps it is my poor technique !

boa sorte,
Brian

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Post by rjlittlefield »

NU, you're accumulating quite a collection of nicely done microscope images. I'm impressed at how quickly you've made the transition from insects to protozoa!

BJ, thank you for this observation about the flagella. I imagine this would also solve the puzzle of the missing flagella in Charles Krebs' Volvox HERE ?

--Rik

NikonUser
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Joined: Thu Sep 04, 2008 2:03 am
Location: southern New Brunswick, Canada

Post by NikonUser »

Thanks for the ID Brian.
Thanks Rik.

Title changed
NU.
student of entomology
Quote – Holmes on ‘Entomology’
” I suppose you are an entomologist ? “
” Not quite so ambitious as that, sir. I should like to put my eyes on the individual entitled to that name.
No man can be truly called an entomologist,
sir; the subject is too vast for any single human intelligence to grasp.”
Oliver Wendell Holmes, Sr
The Poet at the Breakfast Table.

Nikon camera, lenses and objectives
Olympus microscope and objectives

BJ
Posts: 355
Joined: Sat Sep 29, 2007 10:53 am
Location: England

Post by BJ »

Rik,

yes same comments apply to Charles posting. i did actually compose a long (probably too long !) response to Charles post but it got lost in cyberspace and i did not get the opportunity to return to it (apologies).

in haste,

brian

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