Removal of a single polyp

[GhostCon1]

I am wondering if it is possible to remove a single polyp from an acropora sp. and not harm the coral permanently. If I have to frag a small piece that is fine, but I have no idea how to extract the polyp itself.

The reason I want to do this is there is a science fair at my college and I am doing a booth for our biology club with a handheld microscope and examining things up close for the kids.

I think it would be cool to show a polyp to them and maybe the zooxanthellae living in the polyp (assuming the polyp survives extraction and/or transport).

Thanks everyone.

 

[OwenInAZ]

The zooxanthelle are probably too microscopic to see with a handheld 'scope. If it were me, I think it'd be cool to just look at a couple different types of coral up close, so frags would do.

 

[GhostCon1]

The zooxanthelle are probably too microscopic to see with a handheld 'scope. If it were me, I think it'd be cool to just look at a couple different types of coral up close, so frags would do.

It has 200x magnification:worried:

 

[Agu]

First of all I don't see why you need a single polyp ? Wouldn't a small frag work just as well ? You could just scope in (pun intended ) on a single polyp.

 

[GhostCon1]

I don't think I would be able to get the polyp to open up at the booth in the gymnasium.

 

[ousnakebyte]

This is a compound light microscope, not a dissecting scope, right?

Really, to truly appreciate the coral polyp, a dissecting scope is best, in my opinion. Otherwise, you just see a dark blob. With a dissecting scope, just take a few polyps - two to three, maybe four, and you will be able to see the zoox speckles within the tissue easily. And, zoox won't just be in the polyps itself but in the surrounding base flesh as well. If you are still and don't rattle the table too much, the polyp(s) will emerge enough to see visible zoox.

But, a REALLY good candidate for this is P. damicornis. I have used this coral MANY times for demos, and it is fabulous. The polyps are always out, zoox speckles everywhere. And, if you have a large chunk of it, you can put it in a cup over night and see if it has released any planula larvae - they look like flatworms. If you have enough time, give it a frag plug that has a biofilm on it, and the larvae will metamorphose into a primary polyp on the frag plug. Then, you can have the adult colony there and the primary polyp, and show kids how corals start out life as a tiny pinhead, then grow to HUGE colonies.

Really want to razzle-dazzle 'em, build a small black box, put the adult P. dam in water in the box and have people see the fluorescence with Night Sea:

Night Sea

If you are set on the single polyp, you can use a diamond wheel dremmel to get the single polyp with corallite extracted, then use fine-tipped tweezers (I recommend two) to gently crack open the corallite, exposing the polyp. If you are careful, you might be able to open up half the polyp and expose the mesenteries too.


If you are using a compound light microscope, here is another fun demo. Get some aptasia - they are always around... Have a cup for holding your aptasia and get a sharp razor blade and cut a tentacle from an adult and place the tentacle on your microscope slide - well slides are good for this. Then, take a drop of DI water and drip it on the tentacle. Look through the scope (200x should be plenty for this), and you should see the nematocyst threads discharge from the cnidocytes. It's amazing the speed at which they come bursting out of the capsule, and the are LONG. It's hard to believe that that whole thread is coiled up in that tiny cell. Really, I have to focus on one spot and wait for a thread to appear. If I am scanning around, I'll miss the actual discharge.

What happens - explanation. This demonstrates diffusion by osmosis. Water is going to move to the area of higher solute concentration, in this case to the inside of the cells, passively across the membranes. As the intracellular pressure rises, the cnidocyte cap bursts, expelling the nematocyst thread.

Eventually, you'll need a new tentacle.

Have fun.

Cheers
Mike

 

[GhostCon1]

This is a compound light microscope, not a dissecting scope, right?

Really, to truly appreciate the coral polyp, a dissecting scope is best, in my opinion. Otherwise, you just see a dark blob. With a dissecting scope, just take a few polyps - two to three, maybe four, and you will be able to see the zoox speckles within the tissue easily. And, zoox won't just be in the polyps itself but in the surrounding base flesh as well. If you are still and don't rattle the table too much, the polyp(s) will emerge enough to see visible zoox.

But, a REALLY good candidate for this is P. damicornis. I have used this coral MANY times for demos, and it is fabulous. The polyps are always out, zoox speckles everywhere. And, if you have a large chunk of it, you can put it in a cup over night and see if it has released any planula larvae - they look like flatworms. If you have enough time, give it a frag plug that has a biofilm on it, and the larvae will metamorphose into a primary polyp on the frag plug. Then, you can have the adult colony there and the primary polyp, and show kids how corals start out life as a tiny pinhead, then grow to HUGE colonies.

Really want to razzle-dazzle 'em, build a small black box, put the adult P. dam in water in the box and have people see the fluorescence with Night Sea:

Night Sea

If you are set on the single polyp, you can use a diamond wheel dremmel to get the single polyp with corallite extracted, then use fine-tipped tweezers (I recommend two) to gently crack open the corallite, exposing the polyp. If you are careful, you might be able to open up half the polyp and expose the mesenteries too.


If you are using a compound light microscope, here is another fun demo. Get some aptasia - they are always around... Have a cup for holding your aptasia and get a sharp razor blade and cut a tentacle from an adult and place the tentacle on your microscope slide - well slides are good for this. Then, take a drop of DI water and drip it on the tentacle. Look through the scope (200x should be plenty for this), and you should see the nematocyst threads discharge from the cnidocytes. It's amazing the speed at which they come bursting out of the capsule, and the are LONG. It's hard to believe that that whole thread is coiled up in that tiny cell. Really, I have to focus on one spot and wait for a thread to appear. If I am scanning around, I'll miss the actual discharge.

What happens - explanation. This demonstrates diffusion by osmosis. Water is going to move to the area of higher solute concentration, in this case to the inside of the cells, passively across the membranes. As the intracellular pressure rises, the cnidocyte cap bursts, expelling the nematocyst thread.

Eventually, you'll need a new tentacle.

Have fun.

Cheers
Mike

Thanks! Too bad I don't have P. damicornis.

 

[ousnakebyte]

It's a weed coral, and many don't want it - mostly b/c it continually releases larvae that then settle next to that prized ORA whatchamajigger and then proceeds to sting it. Ask around; if you were closer, I'd give you several colonies.

Cheers
Mike

 

[billsreef]

I'm out the door so don't have time to get into it, but remind me later...I've a trick for you to relax the polyps so that they can be bothered without closing up

 

[GhostCon1]

I'm out the door so don't have time to get into it, but remind me later...I've a trick for you to relax the polyps so that they can be bothered without closing up

Thanks, unfortunately the presentation is in 1 hour and 7 minutes.

I am going to take some bubble aglae, aiptasia, and a frag of some coral (I can't decide which one, the awesome red planet or the blue staghorn?!?!) for the kids to look at.

 

[billsreef]

Thanks, unfortunately the presentation is in 1 hour and 7 minutes.

I am going to take some bubble aglae, aiptasia, and a frag of some coral (I can't decide which one, the awesome red planet or the blue staghorn?!?!) for the kids to look at.

Sorry I didn't see this earlier. How did the presentation go?

 

[GhostCon1]

Sorry I didn't see this earlier. How did the presentation go?

No problems

It didn't go that bad, I arrived a little bit late and the kids' teachers were kind of rushing them along. Plus we had a dissection of a fish which was a bit more interesting.

I tried to get an aiptasia, didn't go so well. However, I did get an asterina starfish and was able to show that. A few kids liked it and I got some good shots of it.

The bubble algae - I was not able to see the chloroplasts like I thought I would be able to.

All in all, glad for this day to be over, it was an incredibly long one!

Bill,
I would still like to learn that trick of yours :bigeyes:

 

[billsreef]

Bill,
I would still like to learn that trick of yours :bigeyes:

Can't really lay claim to it has "my" trick, but I can certainly pass it along. It's actually fairly simple, but can take several hours or longer. Magnesium sulfate, aka Epsom Salt, works as an anesthetic for invertebrates when the concentration is slowly increased. The slowly part is the trick. Put your specimen in a shallow bowel of SW and wait till it relaxes. While waiting, place some Epsom Salt in a piece of cheese cloth and tie it closed. Once the specimen has relaxed, gently (so as not to disturb the specimen and make it close up) place a corner of that bag of Epsom Salt into the SW and wait. Go have beer, lunch, coffee, whatever. After at least an hour, possible quite longer for some critters, check the reactions of the specimen. When it doesn't react to any disturbance, your done. If your looking to make a preserved specimen in a fully relaxed state, this is also the time to hit with a fixative such as formalin.