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First off I'd like to reccomend the University of Dartmouth's publicly available collection located here. They have both SEM and TEM images of a wide range of organisms and cells from algae to see urchins through everything from cholera to mammalian cells. Images are high quality, fully captioned and properly attributed. I'm a little confused as to the ...


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2019-05-01 Edited: Updated dead links From the comment section: I would go with a cheap one with a magnification of ~40X. According to this source, 10-20X is already sufficient to see large protozoans and algae in a pond. Here some suggestions on what you could look at.


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Just my 2-cents worth as visual add-on to @MattDMo 's answer: Blood smear showing red blood cells and two white blood cells at 400x. Source: Microscope Master Human red blood cells 1000x. Source: Wikipedia Human white blood cells 2000x. The small dots (red arrow) are Diplococcus gonorrhea bacteria (Neisseria gonorrhoeae), each ~0.5 micrometers in diameter....


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Depending on how much detail you want to see, 400X (as Chris commented) is definitely sufficient. Remember, the lens(es) under/over the stage are labeled 10X, 20X, 40X, etc., while the eyepiece is generally 10X or perhaps 20X (multiplying the two together gives the final magnification). If your target magnification is 400X, then get a 400X scope - it doesn't ...


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David Orloff's The Cell – an Image Library has thousands of SEM images.


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I agree with @Jeremias Brand's answer. Pretty much you will have to forget about fluorescence microscopy... you can probably find some dusty old one on eBay in your price range, but it probably won't be any good. However, the good news is that seen that in your comment you mention a) plants, b) blood, c) liquids such as wine, d) food? transmitted ...


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Higher magnification is definitely NOT always better. Indeed, the microscope you are considering is designed for maximum magnification of 1,000x. The 2,000x is achieved by adding 20x eyepieces BUT it creates what is known as 'false magnification'. 2,000x is beyond the resolving power of a light microscope so what happens is that the image is magnified 2,000x ...


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With all respect I think the accepted answer underestimates the quality of current inexpensive instruments. What I have found comparing images on my recently acquired $400 scope to those produced by top-end Nikons is that it produces images which are aesthetically less appealing but nearly identical in detail. Mostly I have used it for fungi, which are ...


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It may be a stellate trichome from a plant. You can find other ones by taking swabs from the onion and nearby plants. cool images here wiki info about trichomes


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Have a look at: XTALENT Image Gallery, more than 600 images, last updated in 2006, though. Dennis Kunkel Microscopy, Inc., "scientific stock photography library of light microscope pictures and electron microscopy images featuring science and biomedical microscopy photos". Iowa State University SEM library, includes pictures submitted by students from ...


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Well it depends on the application. First you have to determine what it is that you want to view under the microscope e.g. an organism such as Drosophila or you want to see microscope slides? In the first case you need to by a dissecting microscope, otherwise you need to by an upright light microscope with the appropriate objective lenses, again depending on ...


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I know this question is going to close. But, if you want to work something you can work on: Cryo super-resolution fluorescence imaging Highlights CryoFM allows imaging of vitrified biological samples with fluorescence microscopy. There are significant challenges to achieve high-resolution cryoFM imaging. Fluorophore characteristics at low ...


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This really depends on the application you have in mind. As with other precision instruments there is a huge range of qualities and applications. If you just want brigth field illumination and look at relatively big things ( approx 100 microns) then you could find something decent for the price you mention if you buy used. But if you want more complex ...


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Does this look like the same bug to you ? . This one is a bulb mite, Rhizoglyphus robini, see here.


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This answer addresses the question of how stains were developed historically, which may bring into perspective your overly modern assumptions. Most of these older (but stil very usefull!) staining techniques, such as haematoxylin (or rather haematein), cochenial/carmine etc. were inspired by the work of textile dyers of that era, starting somewhere in the ...


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It is true for most viruses. They have a size of roughly 1/100 of bacteria (or smaller), so they are too small to be seen in light microscopy. According to Wikipedia the maximum limit with light microscopy is around 1500x magnification (or making structures, which are at least around 200nm in size visible). A lot of viruses are smaller, for example the ...


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This is probably the problem: "We did not prepare the leaf; we just put a small piece of it between two slides.". I suppose you mean you put a leaf fragment between two regular microscope slides, those measuring 26mm * 76mm (1in. * 3in.)? That won't work. Long story short: microscope optics/objectives are designed with a specific working distance in mind, ...


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The usage of "fluorogenic" is typically applied to probes that are not currently fluorescent but can be, typically by some enzyme action or other reaction. For example, see here, here, or here. Essentially they are precursors to the fluorescent molecules of interest. As one example, you could get a higher signal to noise ratio if you only "activated" the ...


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A quick google revealed this slideshow that says the nucleus is the easiest organelle to see. Generally, this is what is taught in schools worldwide. Note that mature red blood cells don't have a nucleus, so this isn't a universal rule. The visibility of the nucleus also changes throughout the cell cycle. In case they are trying to trip you up, double check ...


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The 1.40kX is the zoom (1400x), WD is the working distance (distance between the final lens and the object), 20kV is the voltage used to accelerate the electrons, 20μm is the scale. I'm not aware of the other two.


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My advice is always the same: "first microscope? keep it simple, keep it cheap, but nevertheless: buy something usable". This Olympus GB is, IMHO, "something simple/cheap/usable": These can be bought here second-hand for anything between € 50 and € 100. It's an uncomplicated stand, easy to overhaull yourself. It permits the use of any optics you would ...


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The word to look for is 'Image segmentation'. But also here, it very much depends on what you're looking at. Segmentation and quantification of simple fluorescence images is relatively easy and widely used. It can get very complex depending on how complex the structure is you're looking at. There are machine-learning approaches which are able to distinguish ...


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I think you have a good question, but if you want to get a good understanding of the issues you raise with it, then you really ought to consider spending some time reading this optical microscope primer. In my opinion, you need not bother with taking an undergraduate course at a physical university. As an intro to biology (which is not really necessary if ...


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Take a look at my website which has a section called Images. http://www.hssemgroup.com/ There are more than 13 sites listed which have hundreds of SEM images posted


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To answer your other question, you need a low power (also known as dissecting or stereo) microscope in order to see close-up views of specimens visible to the naked eye. For example, you can see a bee, but you need a stereo microscope to see the wonders of its eye. Similarly, you can see a rock or a diamond but you need a microscope to see the crystalline ...


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It is called a Holliday junction. It forms during recombination.


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Most of the dyes used for visualization bind with a much higher affinity to dsDNA. This would be SybrGreen, EtBr (although this will bind RNA as well). There is a pretty comprehensive website from Life Technologies about Nucleic acid stains that is worth a look. There is as well a publication on this topic: "DNA Staining for Fluorescence and Laser Confocal ...


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The imnstrument is shown here upside down. If it is turned around, it looks like this: The glass disc are placed around the middle tube. The operation principle can be seen in this image: The specimen is placed in the tube in the middle and pushed out by turning the knob at the bottom. The minimal increment for this kind of microtome is 10 micrometers. The ...


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RE: What kind of software you always wanted for light microscopic research, but did not know how to build? I research fruit flies and in this field (and many other insect ecology model systems like beetles, moths, butterflies) we use a lot of visually scored data, e.g. body size, wing size, wing morphology, eye colours, bristle numbers, genital morphology,...


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