Why do fingertips look like raisins when they've been in the water for a while?

To be honest, I didn't check the archives :p

Sixto
95 S420
91 300SE
87 300SDL
83 300SD

It's just God's way of getting us out of the tub. :p If things didn't pucker up, we'd never get out.

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Natalie

I'm really bummed now! They left off the conclusion of the tests:
"CONCLUSION

Our reason for doing this project is so that we can learn more about water and science. We learned
that 40C water will "

Will what? We'll never know now!!!

__________________
past MB rides:
'68 220D
'68 220D(another one)
'67 230
'84 SD
Current rides:
'06 Lexus RX330
'93 Ford F-250
'96 Corvette
'99 Polaris 700 RMK sled
2011 Polaris Assault
'86 Yamaha TT350(good 'ol thumper)

I believe it does have something to do with the osmoregulation of water between your body and the external water source. When you leave your fingers in the water for an extended period of time, your body will push water out since the solution is considered to be "hypotonic". In essence, you are losing water out of your body to the external water source and you are "shriveling" up in the process.

__________________
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1960 MB 190Db w/ full sunroof
1985 Toyota Pickup
2006 Honda Odyssey EXL R&N
2001 VW Jetta GLS TDI

Wow!
Did you make that up all by yourself?

__________________
past MB rides:
'68 220D
'68 220D(another one)
'67 230
'84 SD
Current rides:
'06 Lexus RX330
'93 Ford F-250
'96 Corvette
'99 Polaris 700 RMK sled
2011 Polaris Assault
'86 Yamaha TT350(good 'ol thumper)

I thought it was the other way around - water flows through a semipermeable membrane towards the side with more dissolved stuff in it. The reason you can crisp a floppy lettuce by leaving it in water for a while. So, your might pucker up because you have drank in your bathwater (through your skin, not your mouth ).

I think that the skin expands for the reason that JJL mentions. The reason that it folds is that there is an abundance of connective tissue that prevents the skin from separating from the underlying tissues. The connective tissue is not perfectly evenly or randomly distributed but is preferentially distributed along the axis of the finger. So when water is absorbed it swells the tissue bulging it outward except where the connective tissue locks it firmly in place.

I made that up, but it sure sounds authoritative, doesn't it?

Botnst

How come the wrinklage is mostly in the fingertips and toetips(?) Most of me is in the water when I swim.

I won't ask about the other situation :p

Sixto
95 S420
91 300SE
87 300SDL
83 300SD

Sixto, I got this from:
http://www.aboutchildrenshealth.com/library/weekly/aa033101a.htm
Looks like JJL came closest, but his was still incomplete. JJL, what grade would you give your cell phys answer? I figure its about a B-, but still better than anybody else's. The one-eyed man rules the kingdom of the blind!

Botnst


Place one finger into the "water" and another finger into the "salt water."

Your fingers should be in the water at least up to the first joint. Now sit there and wait......... Keep waiting........... Not yet............Almost done...........

After 5 minutes, take your fingers out of the water and compare them. You should find that the plain water finger is more wrinkled than the salt water finger.

Why? What makes your finger wrinkle?

Each of the cells in your body is like a tiny water balloon. There is a membrane surrounding the cell, much like a rubber balloon. This membrane will let water move through it, but the direction the water moves (in or out) depends on salt and other dissolved chemicals in the water. The water will move towards the highest concentration of salt. If the salt is more concentrated on the inside of the cell, as with the plain water, then water moves into the cell. This makes the cell bigger. If all of the skin cells on your finger get bigger, you wind up with a skin that is too big for your finger. This extra skin makes the wrinkles.

Don't worry. After your finger has been out of the water for a while, then the skin will shrink back into place. At this point, Scott asked his wonderful question. He asked if that meant that you would not get as wrinkled if you swam in the ocean. He was exactly right, as you can see from the finger that was in the salt water.

With more salt in the water, less of it moves into the cells. Your finger skin does not get much bigger and you get far fewer wrinkles. Before all of you adults get excited, no, soaking in salt water will not cure the wrinkles you get as you get older.

Nice one Botnst! Your marking is harsh, though..I'd give myself an 'A'

..but we still haven't answered the question of why fingertips pucker more than elsewhere on the body. The skin doesn't seem particularly different ..perhaps nobody knows, its not the kind of thing you would get funding to study (could be wrong about that - some weird stuff gets funded!).

That's why you didn't get the 'A'!

You're right about the complete answer, though. The quest continues!

With all these Benz owners, you'd think at least one of them would be a physician, or have they all gone to the dark side: bought Lexi?

Botnst