They are chemical bonds.
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because they're chemical names,mono and di .....are ionic charges of the elements.
Not just for sugars or chemicals. These are prefix rooted from Latin and used very often in science and maths.
Mono =1, eg. monoxide
Bi =2,, eg bicycle
Tri =3 eg.triangle
Quad =4, eg.quadratic
Pent=5, eg.pentagon
...
poly =many, eg.polygon
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