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Can two monomers form a polymer?

I know polymer is "many" monomers joined together, but how "many" is many? Can 2 monomers considered as a polymer?

thanks :smile:
A polymer is a long chain of monomers- hundreds of monomers or even thousands, you wouldn't call two monomers bonded together a polymer- though i do not know what you'd call it(i guess something like a "dimonomer"), but it can't be considered a polymer
Original post by Abraham_Otaku
A polymer is a long chain of monomers- hundreds of monomers or even thousands, you wouldn't call two monomers bonded together a polymer- though i do not know what you'd call it(i guess something like a "dimonomer"), but it can't be considered a polymer

hello, thanks for your message.

but, since disaccharide is still considered as a "carbohydrate polymer" (which consists of two monosaccharides, and thus 2 monomers), wouldn't two monomers still considered as a polymer?
Original post by BrightBlueStar11
hello, thanks for your message.

but, since disaccharide is still considered as a "carbohydrate polymer" (which consists of two monosaccharides, and thus 2 monomers), wouldn't two monomers still considered as a polymer?

hmm.. I guess those would be considered the simplest forms of a polymer
im pretty sure you can't have two monomers forming a polymer - but you can react 2 monomers to form a new monomer.
an example is condensation polymerisation where you react 2 monomers with different functional groups together, but the key point is that this reaction forms a whole new monomer made up of the two, rather than it being made from 2 separate monomers,,,
Original post by BrightBlueStar11
I know polymer is "many" monomers joined together, but how "many" is many? Can 2 monomers considered as a polymer?

thanks :smile:

"poly" means "many"

two monomers gives a dimer
three monomers gives a trimer
four monomers gives a tetramer

Poly, in this context means a huge number, maybe 60,000 up to more than 100 million
Original post by charco
"poly" means "many"

two monomers gives a dimer
three monomers gives a trimer
four monomers gives a tetramer

Poly, in this context means a huge number, maybe 60,000 up to more than 100 million

thanks
hello, can I ask why disaccharide is considered as a carbohydrate polymer?
Original post by BrightBlueStar11
thanks
hello, can I ask why disaccharide is considered as a carbohydrate polymer?


can you provide a reference?
Original post by charco
can you provide a reference?

sure,

"A disaccharide is a carbohydrate polymer composed of two sugar monomers (monosaccharides) which are joined by a glycosidic bond formed by a condensation reaction.", which is from "school of biomedical sciences WIKI"

Also, from AQA A-level Biology revision guide, it says that "a polysaccharide is formed when more than two monosaccharides are joined together by condensation reactions"

idk it is so confusing like different resources tell different ideas
(edited 1 year ago)
Original post by BrightBlueStar11
sure,

"A disaccharide is a carbohydrate polymer composed of two sugar monomers (monosaccharides) which are joined by a glycosidic bond formed by a condensation reaction.", which is from "school of biomedical sciences WIKI"

Also, from AQA A-level Biology revision guide, it says that "a polysaccharide is formed when more than two monosaccharides are joined together by condensation reactions"

idk it is so confusing like different resources tell different ideas

Do you have a reputable reference, not a wiki?
You may think that I'm being picky, but it's easy to source non-academic websites that have been thrown together for commercial purposes:


Carbohydrates, the most abundant biomolecules on earth, are widely used by organisms for structural and energy-storage purposes.
Carbohydrates include individual sugar molecules (monosaccharides) as well as two or more molecules chemically linked by glycosidic bonds. Monosaccharides are classified based on the number of carbons the molecule as trioses (3 C), tetroses (4 C), pentoses (5 C), and hexoses (6 C). They are the building blocks for the synthesis of polymers or complex carbohydrates.
Disaccharides such as sucrose, lactose, and maltose are molecules composed of two monosaccharides linked together by a glycosidic bond.
Polysaccharides, or glycans, are polymers composed of hundreds of monosaccharide monomers linked together by glycosidic bonds. The energy-storage polymers starch and glycogen are examples of polysaccharides and are all composed of branched chains of glucose molecules.
The polysaccharide cellulose is a common structural component of the cell walls of organisms. Other structural polysaccharides, such as N-acetyl glucosamine (NAG) and N-acetyl muramic acid (NAM), incorporate modified glucose molecules and are used in the construction of peptidoglycan or chitin.

Taken from https://courses.lumenlearning.com/microbiology/chapter/carbohydrates/
The term ‘sugar’ refers to sucrose while ‘sugars’ refer to all monosaccharides and disaccharides. ‘Free sugars’ refer to mono- and disaccharides added to food by the manufacturing industry. Examples of monosaccharides include glucose (dextrose), fructose (levulose), galactose, xylose, and ribose. Monosaccharides are the building blocks of disaccharides such as sucrose and lactose, and polysaccharides such as cellulose and starch. Sucrose, the sole focus of this Encyclopedia article, is a disaccharide made up of glucose and fructose molecules in a one-to-one ratio. Other disaccharides of relevance include lactose (milk sugar) found in milk and dairy products. Lactose comprises the monosaccharides glucose and galactose and maltose, comprising two glucose molecules, which occurs in barley, wheat, and malt.

Dietary Sugar

N.P. Steyn, N.J. Temple, in Encyclopedia of Toxicology (Third Edition), 2014

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