The following image comes from this resource and is labelled to show which structure is which (Walter Dioni, http://microscopy-uk.org.uk/mag/indexmag.html?http://microscopy-uk.org.uk/mag/artfeb04/wdstem.html):
ep = skin of the stem – col = colenchyma – par = cortical parenchyma (colenchyme + parenchyma form the cortex) –cb = cambium interfasciculaire – Paq.vasc. = package or vascular bundle formed by the phloem (ph) and the xylem (xy). Later it will be seen with more details – moelle, the central cylinder of parenchyma (the pith). Cambium plus pith form a central cylinder: the stele. The raphides are oxalate of calcium needles secreted by some cells. Here, the edges of the razor blades have cut an epithelial cell full of raphides throwing them on the cuted surface
I think the dark brown/black areas between cells in my photos below are vascular bundles seen end on, with the thick spiral supporting structure shown in the photos in my photos of the vertical section seen at the link above acting to block out light when seen end on. I can not identify raphides in the pictures below but I think I may have seen them in another post – see http://roslistonastronomy.uk/plant-stem-from-kitchen
My photos from today:
x10 objective, bright field:
x20 objective, bright field:
x32 objective, bright field:
x10 objective bright field crossed polarisation – varying rotation angle of one filter (below):
I bought my wife some tulip cut flowers last week – an ideal place to obtain a short section of stem. The biggest problem was finding a fresh sharp blade to cut it. Ideally, a new razor blade would do the job but I did not have one to hand!
An excellent resource which discusses what can be found in such sections can be read at http://microscopy-uk.org.uk/mag/indexmag.html?http://microscopy-uk.org.uk/mag/artfeb04/wdstem.html
In particular, see the image that author has published on that page of the spiral reinforcing structures in the vascular bundles of the stem – you can see these spiral reinforcing structures, cell walls, chloroplasts in my images below – although there are also linear artifacts from my cuts/folding tissue as I cut (basically it goes crinkly – although I floated the section on a drop of water on the slide to try and smooth this out. It is for this reason that I have not published any images of the Helicon Focus 3D depth maps – as the crinkling dominates the depth maps).
The following photos show a piece of plant stem I cut up from a pot in our kitchen this evening. I don’t know what the plant was. It shows may chloroplasts and cell walls.
x20 bright field:
x20 objective Phase Contrast I annulus:
x32 objective Phase Contrast I annulus:
The following two photos are both taken using the x32 objective and phase contrast I annulus. The long thin features look like bacteria but they did not move so I wonder if they come from the plant? I wonder if they might be raphides. Raphides are oxalate of calcium needles secreted by some cells. Here, the edges of my blade may have cut an epithelial cell full of raphides throwing them on the cut surface, in a similar way to that experienced by Walter Dioni in his post on http://microscopy-uk.org.uk/mag/indexmag.html?http://microscopy-uk.org.uk/mag/artfeb04/wdstem.html
This sample was collected from our garden 7 days ago and kept in an open jar of water.
The contents of the jar had separated into a top layer of moss floating on the top, an intermediate layer of very cloudy water and a bottom layer of debris on the bottom of the jar. I have tried to sample all three layers in the pictures below.
x20 objective bright field sample from bottom of jar – debris layer. This shows large numbers of bacteria.
x32 objective bright field bottom debris layer:
Moss 7 day culture bottom jar layer video x32 objective Phase I annulus:
x20 phase contrast I debris layer bottom jar:
x32 objective phase contrast I debris layer jar:
x20 objective phase contrast I cloudy liquid layer between debris on bottom and floating moss – I am not convinced that this is phase contrast even though I labelled it as such – looks like bright field to me now:
x20 bright field liquid layer between debris and moss – video:
x20 bright field one single moss plant from the floating moss on top of the jar. If you look carefully you can see hundreds of bacteria surrounding this plant:
Tardigrades are water-dwelling, eight-legged, segmented micro-animals. They were first discovered by the German zoologist Johann August Ephraim Goeze in 1773. The name Tardigrada was given three years later by the Italian biologist Lazzaro Spallanzani. They have been found everywhere: from mountain tops to the deep sea and mud volcanoes (Wikipedia).
Tardigrades, often called water bears or moss piglets, are near-microscopic animals with long, plump bodies and scrunched-up heads. They have eight legs, and hands with four to eight claws on each. While strangely cute, these tiny animals are almost indestructible and can even survive in outer space. Tardigrade is a phylum, a high-level scientific category of animal. (Humans belong in the Chordate phylum — animals with spinal cords.) There are over 1,000 known species within Tardigrade. Water bears can live just about anywhere. They prefer to live in sediment at the bottom of a lake, on moist pieces of moss or other wet environments. They can survive a wide range of temperatures and situations (https://www.livescience.com/57985-tardigrade-facts.html)
I went looking for tardigrades today in St Michael’s church graveyard in Lichfield, Staffordshire, UK. No success – sadly – so you won’t see tardigrades in the photo and video below. However, the samples I obtained from moss on gravestones, some lichen off trees and a sample from a wood chipping pile, revealed a range of life shown in the video below.