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Can crystals come from living things?
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sunfish123
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- Project Question: Does evaporation affect the rate of sugar crystal growth?
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Can crystals come from living things?
My son is doing a science experiment growing sugar crystals. In our research we came across a book that said that flour is not a crystal because it comes from wheat which is a living thing. However, sugar comes from sugar cane, which is a living thing. Please help clarify!
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deleted-71447
- Former Expert
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Re: Can crystals come from living things?
Hi sunfish123,
Welcome to the Ask an Expert forums.
Living things do produce body parts with crystalline structure. For example
http://www.nationmaster.com/encyclopedia/Seashell
If you can post the original quote, we might be able to clear up any confusion related to terminology or poor writing in the book.
I hope that helps.
Chris
Welcome to the Ask an Expert forums.
Living things do produce body parts with crystalline structure. For example
http://www.nationmaster.com/encyclopedia/Seashell
If you can post the original quote, we might be able to clear up any confusion related to terminology or poor writing in the book.
I hope that helps.
Chris
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deleted-71588
- Former Expert
- Posts: 1297
- Joined: Mon Oct 16, 2006 11:47 am
Re: Can crystals come from living things?
There are a LOT of elementary science books that have a lot of outdated or misinformation or easy to misinterpret information in them. There is also a lot of scientific "jargon" that has changed over the years and there has been a lot of increased understanding of things which alter the classification of things.
Bones are also good examples of things that are "crystaline" in nature produced by vertabrate animals (living things). If you break bones, they fracture along crystal boundaries and like puzzle pieces, you can usually figure out how they once fit together.
Wheat Flour is mostly starch (polymerized glucose) which is an "organic" compound. The word "organic" is one of those "jargon" words that has multiple meanings and the "common" usage differed over the years even within a given scientific disipline. "Organic Chemistry" is the study of chemical compounds that contain carbon but curiously usually excludes things like diamonds and coal which are crystaline forms of carbon (which are studied in physical chemistry which is often included in a course of "Inorganic Chemistry"). Chemicals which are polymers don't have a regular structure so they aren't crystaline.
Plants rarely produce crystals and primarily produce "organic" (carbon based) compounds. The glucose in sugar cane or sugar beets or maple sap is not in its crystaline form within the plant. In order to obtain a crystaline form, it has to be processed.
How does one explain to an elementary student that wheat flour is not a crystal? At the lower grade levels, how does one demonstrate the lack of a crystaline structure? If you grind salt or sugar crystals small enough like powdered sugar, how can you demonstrate that they are different than finely ground wheat flour? All I can say is that it isn't easy and many fail in their attempts. The good ones do it oh so deceptively simplistically well that it makes sense and withstands rigorous scientific evaluation, but in reality, it is the result of an extremely complex thought process in how the explaination goes so that it is very hard to be misinterpreted by most people and is scientifically correct to the current level of understanding.
Bones are also good examples of things that are "crystaline" in nature produced by vertabrate animals (living things). If you break bones, they fracture along crystal boundaries and like puzzle pieces, you can usually figure out how they once fit together.
Wheat Flour is mostly starch (polymerized glucose) which is an "organic" compound. The word "organic" is one of those "jargon" words that has multiple meanings and the "common" usage differed over the years even within a given scientific disipline. "Organic Chemistry" is the study of chemical compounds that contain carbon but curiously usually excludes things like diamonds and coal which are crystaline forms of carbon (which are studied in physical chemistry which is often included in a course of "Inorganic Chemistry"). Chemicals which are polymers don't have a regular structure so they aren't crystaline.
Plants rarely produce crystals and primarily produce "organic" (carbon based) compounds. The glucose in sugar cane or sugar beets or maple sap is not in its crystaline form within the plant. In order to obtain a crystaline form, it has to be processed.
How does one explain to an elementary student that wheat flour is not a crystal? At the lower grade levels, how does one demonstrate the lack of a crystaline structure? If you grind salt or sugar crystals small enough like powdered sugar, how can you demonstrate that they are different than finely ground wheat flour? All I can say is that it isn't easy and many fail in their attempts. The good ones do it oh so deceptively simplistically well that it makes sense and withstands rigorous scientific evaluation, but in reality, it is the result of an extremely complex thought process in how the explaination goes so that it is very hard to be misinterpreted by most people and is scientifically correct to the current level of understanding.
-Craig