Microscopy ideas version 2.1

Something new: microscopy for the masses
In 2011, my 2010 children's book, Australian Backyard Explorer, won the Children's Book Council of Australia Eve Pownall Book-of-the-Year award for information books. This is a combination of the sort of science you will see here and a lot of Australian history. My reason for mentioning it here is that I have since written a sequel, Australian Backyard Naturalist, which will be out in May 2012. The relevance here, is that I wrote a lot of stuff that we later decided was too advanced for the readership. With the book now on the presses, I am now converting that extra material into blog entries. I have started with microscopy, and the material can be found at Old Writer on the Block, which is, in theory at least, my writing blog. Hey, it's my blog, I get to make the rules.

This is a set of hints and ideas for people who have access to a microscope: the ideas are only as good as you make them. It is a cooperative effort and owes a lot to the ideas shared by a group of people on the ABC Science-Matters List, whose names appear at the end of this page. It is still being added to . . .

Topics

Aging fish
Animal fur
Cheek cells
Fibres
Forehead mites
Granite fragments
Green slime
Growing Crystals
Home crystals
Leaf Epidermis
Making a microtome
Metal Crystals
Mosquito wrigglers
Moss Animals
Moth wings
Plant Details
Pollen Cell Germination
Red blood cells
Seeds Germinating
Seeds that cling
Slowing Animals Down
Sponge spicules
Sundews
Water fleas
Future plans
Other pages on this site

Ideas for monocular microscopy

See also ideas for binocular microscopy and ideas for video microscopy

Seeing red blood cells
You will need a Petri dish, either a tadpole or several paper tissues (paper towel will do), a small fish like a guppy or a minnow, a monocular microscope, and a good light source. You will also need a net, but a large beaker is often better for catching a fish or tadpole gently. All you have to do is pour water from the large beaker into a smaller beaker until one animal transfers over.

You will need to work quickly. The tail of a tadpole or fish is thin, flat and transparent, which means you can actually see through it, and see the capillary vessels inside the flesh. Get your microscope set up first, and focus it on a small piece of wet paper tissue sitting in the bottom of the Petri dish. If you have an iris diaphragm, close this down as far as possible, and make sure you know how to move the dish so the tissue catches the light.

Both tadpoles and fish breathe through gills, so it is best if you do this with somebody else, who can be given the job of moving the animal so the clear part of its tail is in the light. Scoop your fish or tadpole from the water. If it is a tadpole, just tip it into the dish, and start looking after a minute, put the dish gently into the tank, let the animal swim away, and if necessary, choose another one.

With a fish, try to lay the fish with its head on the wet tissue, and cover the head with a second layer to stop it flapping around. Try to avoid touching the fish as you will damage its scales and whether you are using a tadpole or a fish, wash your hands afterwards, before you touch food or drink.

The main thing to remember is that even the thin tail will have a number of layers that the microscope can 'see', but because the flesh is clear, you can focus up and down until the blood vessels are clearly in focus.

This will help you to do this better


Looking at green slime
You will need a microscope and light source, slides and one well slide, cover slips, a needle to lay the cover slips down, a medium size "camel hair" brush, and an eye dropper or a Pasteur pipette, which is just an eye dropper with a long drawn-out point.

Most ponds and still water will develop a collection of life over time, and if you take some green slime, you will normally take a good sample of this life, along with the "slime", which is actually an assortment of algae.

The mistake most beginners make is to put too much 'gunk' onto a slide. Your microscope works when light shines through the stuff on the slide, and your cover slip has to lie down flat. If there is too much gunk, you can't see through it, and the cover slip does not settle down properly.

Take small amounts, and spread even that out with a brush. If you have a fish tank, some of the most interesting gunk comes from the filter. Stir this up a bit, and then take some of the material with an eye dropper and put it in a Petri dish. With a black background and a strong light, you should be able to see if there are any tiny animals in the water. If there are, use an eye dropper to take a sample. If there are no animals, use a flat slide, if there are animals in the gunk, use a well slide.

With any sort of luck, you will strike it lucky when you switch to high power, and you will see some Paramecium or other of the larger wee beasties that often live in water. Keep an eye out also for filamentous algae like Spirogyra, which is easy to spot because it has spiral chloroplasts.

This will help you do this better


Leaf Epidermis
You will need a microscope and light source, slides, cover slips, and a needle to lay the cover slips down. A few stains may also come in handy.

The epidermis of a leaf is a single layer of cells. With care, you can peel it off and make a wet mount of it. It is a single layer of cells, so you should be able to see detail in the cells.

This will help you understand


Mosquito wrigglers
You will need a microscope and light source, slides and at least one well slide, cover slips, a needle to lay the cover slips down, a medium size "camel hair" brush, and an eye dropper. If you can buy some, you need some Gurr's Water Mounting Medium, or some gum arabic but don't ask me how to use gum arabic: I don't know! So discover how, and share the knowledge with me! For some ideas, see Slowing Animals Down.

With luck, you will be able to see how the mosquito breathes, and you should be able to see its digestive system, but you should be aware that the wriggler will drown when it cannot get air through its siphon.

This will help you understand


Moth and butterfly wings
Butterfly wings are particularly interesting, because, strange as it may sound, there are no colours in them or at least there are no pigments. The moths and butterflies are called the Lepidoptera, which means "scale wing", because their wings are covered in very fine scales, and in the case of the butterflies, these scales produce the effect of colour because of the way they catch the light.

Even though you will probably want the higher magnification of a monocular microscope, you will probably need to use reflected light to see any detail, so think about using a bright reading lamp as your light source.

The most obvious question should be where do the colours come from? Take a close look at the scales and see if they are coloured, then scrape some off and make a wet mount of them.

This will help you understand


Fibres
You will need a microscope and light source, slides and one well slide, cover slips, a needle to lay the cover slips down, a medium size "camel hair" brush, and an eye dropper. If you are looking at fabric fibres, you will probably need some tweezers.

If your microscope came with some sort of grid, you may be able to estimate the diameters of the fibres, as well as noting variations in the diameter, any markings or scales on the fibres, and how they terminate or break. Many fibres will take up a variety of dyes, so there is a whole new line of enquiry open there!

See also the entry on animal fur.

This will help you understand


Water fleas
You will need a microscope and light source, well slides, cover slips, a needle to lay the cover slips down, a medium size "camel hair" brush, and an eye dropper. You will also need a water culture that has been maturing for a few weeks in large PET bottle which is about two thirds full. If you fill this to the top with water, the surface area becomes smaller, and oxygen levels drop, forcing many of the animals up to the surface, where they can be picked up with an eye-dropper.

This will help you understand


Animal fur
A note from Darren Jones.

This might be a little too techo for the kid at home, but did you know that you can identify most Aussie mammals down to species (and certainly to genus) level using a (guard) hair and a microscope? Guard hairs being the longer, thicker (often darker) hairs in the mammal coat, i.e., not the little, soft downy type hairs.

You use 2 diagnostic criteria, the scale pattern on the hair, and the appearance of the hair in cross-section. To get a scale pattern, you paint clear nail varnish onto a microscope slide, lay the the guard hair on the varnish, and quickly peel the hair off when the varnish has dried.

To get a hair cross-section, ecologists have a special metal slide, same size/shape/thickness as a normal glass microscope slide, but with a hole of 1-2mm diameter through it. You take a little bundle of fine frayed nylon cord, and pull this through the hole so as it makes a snug, but not too tight, fit. There should be frizzy bits of nylon sticking out on each slide of the slide in a sort of cloud . then you push a guard hair (or 2 or 3) end-on through the hole.

The nylon fibres hold the hair(s) in place. Get a sharp razor blade, and run this quickly and smoothly at ~30 degrees angle across the slide, trimming away the nylon cloud. Do this on both sides- now you've got a 'slice' of hair in the hole held in place by the nylon threads.

Identifying the beast from whence your hair came is a descriptive/observational exercise, whereby you use a key to different species/genera hairs. The name of the key I used as an ecology undergraduate escapes me, but I'm sure any Aussie zoologist would know [I am still looking, help needed, pm]. It's easy to use, with photos and drawings of patterns to compare to.

This method is a great way to find out what owls, snakes, foxes, cats, etc. have been eating when you go through their droppings, and also a way to work out what spp. are living in an area without trapping them- you make a 'hair trap', a sticky piece of tube or some such that the animals will squeeze through or brush past (if you put the trap in the right place) while going about their daily business. The hairs stick, you simply collect them and identify them.

This will help you understand


Cheek cells
You will need a microscope and light source, slides, cover slips, and a needle to lay the cover slips down. A few stains may also come in handy. You will also need something like a coffee stirrer made of wood that you can use to gently scrape the inside of your cheek, where cells are always sloughing off. Make a wet mount, and you are on your own.

This will help you understand


Growing Crystals
You will need a microscope and light source, slides, an eyedropper, some paper towelling, and soluble material such as sugar and salt, and enough chemical knowledge to judge whether or not the salts can damage the microscope, in which case you will need a Petri dish to protect the microscope. If you are in ANY doubt, assume that the material will cause problems.

The idea is simple: make a saturated solution of a salt, place a drop on a slide, spread it across the slide, set the slide on the paper towel to clean up any spillage, then place the slide carefully on the microscope stage, and wait for it to dry. The crystals will generally be long and needle-like because of the way the drying proceeds: I leave it as a challenge to find a way of producing larger, more normal slides under these conditions, noting only that a lid for the Petri dish might be a good start.

This will help you understand


Slowing animals down
Slowing down animals Aside from Gurr's Water-mounting medium (mentioned above), there are several other possibilities.

A solution of 10 g methyl cellulose in 90 mL water will produce a syrup that will slow most animals down. You can also add 2-3 grams of gelatin to 100 mL of cold water and heat this while stirring. Cool the gelatin solution back to room temperature and add one drop of pond water to one drop of gelatin solution. Alcohol mounts will kill the animals, but a 1% solution of magnesium sulfate will just anaesthetise them. You can also try grinding up a small piece of face tissue and adding the fibres to the pond water to tangle the animals up.

I have never tried this, but I suspect that water-based PVA glues might also be used, but it will probably ruin the slides.

This will help you understand


Sponge spicules
The small sponges known as siliceous sponges have skeletons made up of pieces of silica called spicules. To see these, treat a small piece of sponge carefully in hot caustic soda or caustic potash (NaOH or KOH). This will dissolve the organic material, and then all you need to is rinse, allow to settle, rinse again, settle again and then pour off the excess liquid carefully.

This could also be interesting


Aging fish by their scales
The scales of fish are supposed to show growth rings. Get some scales and see what you can learn. Are there any stains that make it easier to see the rings?

Hints and ideas will go here when I have some


Granite fragments
You will need well slides, some pieces of granite or similar coarse-grained igneous rock, cover slips, tweezers, and a large sheet of paper to bang the rocks together over. You can also heat granite held in tongs and then drop it into a beaker of water, but this needs adult supervision because of the risks of fire. The best idea is for the adult to stand by with a glass of water to drop on the granite chip if it falls. Sounds like a case for outside work, doesn't it?

The idea is to take some of the small fragments and see if you can find a way of identifying the different minerals, but it could be interesting to see if heat and mechanical action produce any differences. It might be worth looking at any effects of polarised light here, though this sort of work is best done with thin sections of uniform thickness.

If you have access to high power magnification, why not try a few other rocks. Can you see crystals in basalt, for example?

This will help you understand


Pollen Cell Germination
Pollen cells, when they land on the style of a plant, "germinate", growing a pollen tube that finds its way down to the ovule. I have no idea how it navigates, thoiugh I assume it must do so. Also, stray pollen grains will also germinate, but they grow more slowly once again, I have no idea how this is controlled, so there is a lot of digging you can do here, or there is a lot of research to be done. I note that 'self' pollen is often retarded in its growth, so that the plant is able to favour pollination from another strain of the species another fertile area to explore.

Some years ago, I tested two species of flower, Plantago lanceolata, which is a weed, and Kunzea capitata, which happened to be growing in my garden. In each case, pollen grains in a wet mount with a few grains of sugar began to grow, but the Plantago caused violent hay fever, and I have never been back to it. You could try different amounts of sucrose, or compare the effects of fructose or glucose: there is lots to do here.

Here are some hints


Mites on your forehead
This one is offered without comment :-)

You can get to know your own forehead mites the following way: stretch the skin tight with one hand, carefully scrape a spatula or butter knife over the skin in the opposite direction, squeezing out traces of oily material from the sebum glands. (Avoid using too sharp an object, such as a glass edge or sharpened knife.) Next scrape the extracted material off the spatula with a cover slip and lower the slip face down onto a drop of immersion oil previously placed on a glass slide. Then examine the material with an ordinary compound microscope. You will see the creatures that literally make your skin crawl.

- Edward O. Wilson, The Diversity of Life, Belknap 1992, 177.

Comment


Making a microtome
ADULT SUPERVISION is essential for this one risks include cuts, burns, fire and possibly broken blades hitting the eye. SAFETY FIRST! SAFETY FIRST!

You will need a bolt with a wing nut to match, safety goggles, a very sharp blade (a cut-throat razor is best, but these are hard to get and hard to sharpen) and an old cutting board. For small items like leaves, you will need a candle, or some other sort of wax. As an alternative, you will need some scrap polystyrene foam which is probably easier to use.

Put the wing nut on the bolt the "wrong way round", with about one full turn of the nut on the bolt, then fill the empty portion of the nut with whatever you want to section. If you need to section a leaf, prop the bolt upright in an old jar or can, poke the leaf in, and then drip candle wax in, until the leaf is surrounded with wax and leave it to set, or cut some polystyrene foam roughly to size and put a piece of leaf between before you force it down into the threaded hole in the nut.

Put on the safety goggles, get the cutting board, and then trim off any bits that are sticking out of the nut (now you will see why the nut is "wrong way round"). Once that is done, you are ready to start sectioning. Turn the nut slightly, so a tiny amount is pushed out of the threaded hole in the nut, and slice.

This will help you understand


Plant Details
Many Australian grasses have silica hairs on them. A good example is Spinifex, which grows on sand dunes, but many other grasses have silica hairs which may repay an examination. Then ask yourself why some leaves are furry, and find out why.

Or you could try taking a closer look at stinging nettles (ouch!). Gardening gloves might be a good idea.

Then how about looking at the fine structures of seeds of different plants, or the detailed structure of a flower, especially the stamens. Cross sections work best under a binocular microscope.

Some comments



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Ideas for binocular microscopy

See also ideas for monocular microscopy and ideas for video microscopy

Moss Animals
You will need a good light source, a Petri dish, a mat of moss and some water and/or alcohol.

There are many animals that live in a moss mat, but they can be hard to flush out. If you slowly add water to a moss mat in a Petri dish, you may be able to persuade the animals to climb up into the dry. Adding alcohol with an eye dropper has the same effect, but you need to watch out for fire, and avoid breathing the fumes. People often use a small amount of formaldehyde (methanal) to flush sea life out of algal mats but this is POISONOUS, and should NEVER be used when you will be hanging over the dish and breathing in the fumes. Ethanol or rubbing alcohol is safer.

This will help you get more out of this


Metal Crystals

Warning: adult supervision needed

A suggestion from Gerald Cairns:

You could examine (under low power) the crystal growth of silver on cast iron chips in a stream of silver containing solution, it's better if the solution is flowing gently. The silver is reduced from solution by metal replacement commonly referred to as diffusion limited aggregation. This process is what we we developed into our 'EFFICAT' System in the mid 1970's and 80s for silver (and other metals) recovery. Students should be able to obtain some silver containing fixer from the local 'friendly' fast photo outlet or photographer. Black and white fixer is best or second best is the Kodak C41 fixer or equivalent.

Note from pm:you could also use silver nitrate solution, but this is corrosive and stains hands etc. Use latex gloves and use a Petri dish on a number of sheets of newspaper to hold everything if you are using silver nitrate solution and try a bit of fine cleaned copper wire in a well slide with a monocular microscope as well. Now back to Gerald:

Gerald: Steer clear of the blood red bleach fix which is so good at oxidising it will reclaim the silver almost as fast as it deposits and your iron chips will disappear. Spill bleach fix on metals and they CORRODE quick time, one of my acquaintances dropped his new Nikon F100 into it accidentally and even though he retrieved it immediately and cleaned it thoroughly it was a write off - that really hurt!

Gerald: An article appeared in Scientific American, I think in the mid 80s on Diffusion Limited Aggregation which described this process very well I thought and this would be worth reading. I have copy but "it is in a box somewhere" the family motto around these parts. :-))

Gerald: I have been away from this since the late 80s and I am not sure what changes if any which have taken place in the fast photo chemistry that may affect the process. If all else fails a standard pregnant solution could be prepared for the purpose.

This will help you understand the chemistry


Seeds that cling
Some seeds make an excellent job of clinging to clothes. Most of these are weeds (you work out why!), but they generally have excellent ways of clinging.

This will help you understand


Sugar, salt, and other home crystals
A moment's thought will reveal that you can't do wet mounts of crystals though this is not completely true, if you look at the piece on granite fragments. But you can't do wet mounts of soluble crystals. You will need a Petri dish, binocular microscope, and fine tweezers.

You may find it interesting to see if you can repeat Pasteur's experiment on a sample of tartaric acid: this comes in two forms, "left-handed" and "right-handed", which form mirror-image crystals. Otherwise, examine different types of sugar from castor sugar to coffee crystals and see what you can see.

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Ideas for video microscopy

See also ideas for monocular microscopy and ideas for binocular microscopy

This section was added after Gregg Thorn reminded me that it is possible to attach various cameras to your computer, and record microscopic detail in living colour, write on the screen of your computer, but the ideas can be applied to a variety of cameras

Sundews
Sundews (Drosera sp.) are insect-eating plants, found in swamps and marshes all over Australia. They have sticky hairs with protein-dissolving enzymes, and when an insect is stuck on a leaf, the enzymes break the insect's protein down to amino acids, and this stimulates the leaf to curl over, slowly, bringing more hairs into contact with the insect, and so holding it better. The process generally takes several hours, so this would be a good case for time-lapse studies.

Gentle people can try feeding a sundew on tiny bits of cheese or meat, but if you are growing a sundew in a pot, you need to use very pure sand, and do not add any fertiliser, because these plants are either smart or lazy enough not to produce the dew if they can get enough nitrogen and phosphorus from the soil.

Sounds like a science project? I thought so as well. Congratulations on having such an excellent idea! There are three other genera in the family Droseraceae: the Drosophyllum of the western Mediterranean, Dionaea, from the Carolinas (USA) and Aldrovanda, described as widespread in the Old World.

This will help you understand


Seeds germinating
Many seeds will germinate happily on most cotton wool: wheat, tomato and radish for three, and they can be observed under the low or high power of a binocular microscope.

This will help you understand



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And now for some help

Seeing red blood cells
The point to remember here is that the red blood cells in the capillaries are under almost no pressure from the heart, so they are moving very slowly, and may even stop at times. You are looking for slow-moving blobs, travelling in the capillaries, which are only just large enough for the cells to pass through in single file.

Because the animal will be feeling some distress, it helps if a second person is watching the stage of the microscope and moving the tail into the light. You may need to focus up and down a bit, so get the person moving the dish for you to warn you if you are likely to crush the animal, and only use the fine focus knob on the microscope.

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Looking at green slime
The trick to getting really nice green slime is to maintain a few cultures in tanks or large open trays. Then you need to 'seed' these with water samples from different places. Carry a few 35 mm film containers and take samples from interesting pools, and always try to include a bit of bottom mud or a few scrapings, especially from rocks.

To get really interesting green slime, you really need a hay infusion to make the growth interesting. Boil up some hay, old grass or whatever in a large pot, and then add it to a bucket, and leave that outside to stand or add a few small slops of water from a pond or stream. I am usually in too much of a hurry, so I have a few old tanks lying around that serve as my main sources, and a few clear PET (soft drink) bottles, half full of water and assorted gunk samples. Leave these on a window will near the sun, and add a bit of the water after you have shaken the bottle.

See also Making a terrarium for some other culturing ideas: the water at the lower end of the terrarium can be remarkably rich in life forms.

To identify your algae, you will need a key (or dichotomous key) to the green algae, or the filamentous green algae

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Leaf Epidermis
The onion is made of a set of modified leaves, with each layer of onion being a single modified leaf. Take one layer, snap it inwards, then pull one half past the other, and you should see a thin tough film like a piece of cling wrap. This is the onion epidermis: put it on a slide, make a water mount, and cover it with a cover slip.

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Mosquito wrigglers
The breeding of mosquito wrigglers is easy enough -- leave a container of water out, with a bit of vegetation in it, and wait a few weeks. Further details may be found in the page on Living things.

Some mosquito larvae, and Aedes australis is one of them, can survive quite happily in a saturated brine solution where there is no competition. Others cannot stand much salt at all. Can anybody see the basis of a science project here? The Aedes genus is probably the best to study, as a number of them seem to be associated with salt marshes around the world. I understand that the Australian one I know (and hate) best has a female that is triggered by the rough sandstone edges of brine pools concentrated by salt spray above the high tide mark. Sydney readers can find these on the shoreline just west of Fairlight beach near Manly, others will have to hunt a bit harder.

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Moth and butterfly wings
One excellent source for moth and butterfly wings is from a spider's web, but light fittings are even better, if you are content with moth wings.

How do you tell a moth from a butterfly? In butterflies, the wings come together, above the body, while in moths, they fold down over the body.

Where do the colours come from in the butterfly? They come from an effect called birefringence, which is far too complex to describe here, but look it up on the Web. Weird moth facts and thoughts:

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Fibres
Remember that you only want a very few fibres, because you need to be able to see through the fibres, and you won't do that if you put a whole mat of them under the microscope.

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Water fleas
Water fleas turn up in all sorts of places. Try scooping some water out of rushes with a bucket on a rope, and pour it into soft drink bottles you will then be able to see small animals in the water when you hold the bottle up to the light. If you add some soda water to the water to increase the carbon dioxide concentration, you will find the water fleas move up to the top of the bottle, which will let you pour them off into another container.

If you have some prepared bottles of green slime, drop a few of the water fleas into one of the bottles and set up a culture for future use.

There are quite a few different small crustaceans that are flea-sized, so look for different behavious in the animals you can see in the source, and compare those that move in different ways.

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Animal fur
You are on your own here, though this looks like an excellent prospect for an honours-level science project. Here is a hint: can you stand the smell of roadkill? It might be an excellent way to take identifiable samples from a variety of mammals.

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Moss Animals
One thing to note: a damp paint brush can be used to pick up any animals you want to mount on slide for closer examination. Avoid using tweezers, as they are bad news for animals.

When you look at these animals, remember that tiny as they are, they are able to feed, avoid danger, and reproduce and all in that tiny space!

Note that I mentioned the problems with using formalin: a small amount of formalin in some sea water will flush all sorts of animals out of mats of coralline algae. Do this in a flat white dish in the open, pick up the animals with an eye-dropper, and put them in a large amount of fresh sea water to reduce the risk to them and you!

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Metal Crystals
The chemical reaction here is a simple one, with a more active metal going into solution as the less active metal comes out. Copper crystals will grow on an iron wired from a solution of a copper salt, silver crystals will come out of a silver solution onto a copper wire, and so on. For more on this, do a Web search on "activity series".

On another tack, did you know that brass, etched with dilute nitric acid, will show interesting patterns? The acid leaves the copper while dissolving the metals alloyed with it. Quite a few metals show interesting crystalline patterns when etched with acid.

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Sundews
Do the plants 'react' faster in warmer temperature? How would you find out? How do different species compare? There is less protein in cheese: does this produce a slower reaction? Do sundews like sugar? Do they react to small pieces of metal or glass?

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Cheek cells
The main thing about animal cells is that they separate very easily, because there are no cell walls between them, and they squish flat, but the contents can be hard to see without stains. If you want to look these up on the Web, it may help to know that they are called squamous epithelial cells.

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Seeds that cling
It follows, if the seeds cling to things, they must have a fine structure with hooks or something similar. To get a range of such seeds, go and roll in some grass, or drag an old woollen garment through some weeds or undergrowth.

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Seeds germinating
Seeds will also germinate in water agar in a Petri dish: add 1.5 grams of agar-agar powder to 100 mL of water, boil it, and pour a layer about 6-8 mm deep into as many dishes as you can fill (if you have a lot, scale up the proportions, but the aim is a 1.5% agar).

Radish seeds can be pressed into this, and if you stand the sealed (so it won't dry out) dish on edge, you can rotate the dish 90 degrees every few days, and see how the root always grows downwards.

Other seeds to use: tomato, most weeds (they have to be good at germinating fast!), wheat, bird seed from a pet shop (NO, it DOES NOT produce birds!), or make your own choice.

Going off at a tangent, many Australian bush plants are fire adapted and may not germinate until they have been heat treated this makes them sprout after a fire. This may also apply in other parts of the world there could be a nice project hiding in there.

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Growing Crystals
You are on your own here for now. There will be a separate page on crystals coming next, when this one is finished.

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Slowing animals down
The two ways of slowing the animals down are: to put barriers in the way, so that the animal can move just as fast, but not as far, and putting the animal in a more viscous solution. There is a third possible way: a 1% solution of magnesium sulfate is supposed to anaesthetise tiny animals, but I have never tried this. Note that 1% here means one gram in 100 mL of water: put a drop of this on the slide and then use a camel hair brush to add the animal.

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Sponge spicules
It occurs to me that you may be able to extract some of the silica hairs from Spinifex grass by a similar method; why not try it?

It also occurs to me that the spicules might survive in bottom ooze: how could you find out?

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Aging fish by their scales
No ideas yet you help! I can publish your e-mail here, if you give me some good stuff! It would probably help if you could work out what forms the annual ring: in trees, it is the smaller cells formed during the winter period, and the large cells formed in summer.

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Sugar salt and other home crystals
Use a bright light, and when the crystals have no colour, look at them against a black background, so they stand out.

Think about comparing glucose and sugar, but you may need to look into ways of growing larger crystals..

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Granite fragments
Granite crystals form slowly, as magma cools over long periods, so the crystals have time to grow quite large. Basalt is molten rock that spills out and cools fats, before large crystals can form, but dikes and sills may cool a little more slowly. Go find out!

Now here is a quote to set you thinking along some other lines:

. . . in the field some amount of information concerning igneous rocks can be obtained by rubbing down the chip on a grindstone and using a whetstone, carborundum file, or water of Ayr stone for the final grinding. By these and other methods . . . there are obtained slices of rocks which, though thick, uneven, scratched, and all that is bad, from the point of view of the professional maker of thin sections, are nevertheless capable of yielding much information. With a pocket lens it is possible to make out from such a 'thin' section the nature of the minerals present, the texture and the nature of the rock.

- Frank Rutley, Elements of Mineralogy, 22nd edition, 1915, p. 104

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Pollen Cell Germination
The main thing is to make sure you have enough pollen. The problem I found was that sucrose grains are typically about 0.6mm across, and this holds up the cover slip, so I tried making sloppy wet mounts and putting the sugar grains in the water outside the cover slip. When the sugar was dissolved, I "sopped up" some of the excess liquid on the far side, away from the dissolving crystals, drawing the sugar solution in. Play with this one I am sure there is a lot to discover!

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Mites on your forehead
Makes your skin crawl, just reading it, doesn't it? Look, don't blame me, I'm just quoting, because I haven't tried this one yet but it sounds like seriously gross fun :-) If there are any typos here, it might be because I keep having to stop to scratch . . .

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Plant Details
Plants that have any sort of texture must have a structure that explains the texture. Furry leaves, slippery leaves, non-slippery leaves, all have secrets to reveal. Of course, if you want to get down to it, you will probably want to make some thin sections as well. That really needs a microtome.

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Making a microtome
As the bolt slowly moves into the nut, the stuff filling the threaded hole is slowly pushed out, just by a tuny amount, and as you slide a sharp blade across the flat surface of the wing nut, you will cut that tiny bit off, producing a thin section that can be mounted on a slide.

The wax may be something of a problem, and you need to be aware that most of the reference books will recommend very nasty chemicals to dissolve the wax this is one of the reasons why polystyrene foam is a good idea. Do some experimenting first: and remember that a piece of foam larger than the hole can always be 'screwed' into the nut.

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work space

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work space

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Worried about copyright? You need to go look at my fine print. Well, maybe you don't after you read the next paragraph, but do it anyhow . . . and to see some more ideas, look at the start of that same page
©The assembler and author of this work is Peter Macinnis -- macinnis@ozemail.com.au, who asserts his sole right to the product as it is packaged here, recognising that many of the ideas are common, and that it uses suggestions from Margaret Collins, Darren Jones, Gerald Cairns and Gregg Thorn, while Bruce Harris must take the blame for triggering the idea in the first place.

Why is the extra help separated from the main text? Because I want you to think first, and see if you can't have good ideas as well.

This material may not be included without permission in any commercial material that is sold or traded, nor may it be incorporated into any product carrying an ISBN or ISSN without express permission. Any non-profit educational or home use is completely acceptable without let or hindrance. Copies of this whole file or site may be made and stored or printed for personal or educational use. Share it in the spirit in which it is shared with you.


This page is http://members.ozemail.com.au/~macinnis/scifun/micrscop.htm. It was commenced on June 3, 2001, and it was last changed on October 22, 2001.

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Work space

This stuff will disappear as it turns into real content above

Note: if you are looking at this testbed version, and you see any ideas that are missing, I welcome suggestions! Please

talk to me!

Ideas to work on


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