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1 Introduction

Structure and function of molecules – sugars and polysaccharides. Another important

polymer in the body is made out of sugars. A polymer is a molecule that is made from

many (“poly”) repeating units (“mer”). They can be arranged into a long chain or into a

branched structure. There are a variety of different sugars in the body; they are either

used for energy or for structural polymers. One of the most important sugars in the

body is glucose (Figure 1.8). Glucose is the sugar that is fed directly into glycolysis, one of

the major energy-generating pathways, and which is regulated by the hormone insulin.

Derivatives of glucose are also common structural sugars making up, for example, our

tendons. Additionally, glycogen is a partially branched polymer out of glucose that is

the major energy storage molecule besides lipids. Due to branching and the α-linkages,

glycogen is a soft material (similar to but even softer than starch). It is stored in granules

in cells (especially muscle cells) and enzymatically broken down when needed.

Figure 1.8: Structure of glucose and polymers of glucose (examples for polysaccharides).

Structure and function of molecules – nucleotides and DNA and RNA. Another group of

materials in the body are the nucleotides or the polymers made from nucleotides, DNA

and RNA. In the case of DNA and RNA, the “mers” of the polymer are nucleotides, which

can carry 4 different bases, and in the sequence of these bases the information of genes