polymer

Examples of polymer in the following topics:

• Types of Biological Macromolecules

  • Most (but not all) biological macromolecules are polymers, which are any molecules constructed by linking together many smaller molecules, called monomers.
  • Typically all the monomers in a polymer tend to be the same, or at least very similar to each other, linked over and over again to build up the larger macromolecule.
  • Examples of these monomers and polymers can be found in the sugar you might put in your coffee or tea.
  • Regular table sugar is the disaccharide sucrose (a polymer), which is composed of the monosaccharides fructose and glucose (which are monomers).
  • Lipids are not polymers, because they are not built from monomers (units with similar composition).

• Hydrolysis

  • Hydrolysis reactions result in the breakdown of polymers into monomers by using a water molecule and an enzymatic catalyst.
  • Polymers are broken down into monomers in a process known as hydrolysis, which means "to split water," a reaction in which a water molecule is used during the breakdown .
  • During these reactions, the polymer is broken into two components.
  • In dehydration synthesis reactions, a water molecule is formed as a result of generating a covalent bond between two monomeric components in a larger polymer.
  • In hydrolysis reactions, a water molecule is consumed as a result of breaking the covalent bond holding together two components of a polymer.

• Dehydration Synthesis

  • In dehydration synthesis, monomers combine with each other via covalent bonds to form polymers.
  • The monomers combine with each other via covalent bonds to form larger molecules known as polymers.
  • As additional monomers join via multiple dehydration synthesis reactions, the chain of repeating monomers begins to form a polymer.
  • There is great diversity in the manner by which monomers can combine to form polymers.

• History of DNA Research

  • Torbjorn Caspersson and Einar Hammersten further showed that DNA was a polymer.
  • Crick and Watson built physical models using metal rods and balls, in which they incorporated the known chemical structures of the nucleotides, as well as the known position of the linkages joining one nucleotide to the next along the polymer.

• Transportation of Photosynthates in the Phloem

  • In seeds and bulbs, food is stored in polymers (such as starch) that are converted by metabolic processes into sucrose for newly-developing plants.
  • Sucrose concentration in the sink cells is lower than in the phloem STEs because the sink sucrose has been metabolized for growth or converted to starch (for storage) or other polymers (for structural integrity).

• The Structure and Sequence of DNA

  • The monomeric building blocks of DNA are deoxyribomononucleotides (usually referred to as just nucleotides), and DNA is formed from linear chains, or polymers, of these nucleotides.
  • In polynucleotides (the linear polymers of nucleotides) the nucleotides are connected to each other by covalent bonds known as phosphodiester bonds or phosphodiester linkages.

• Connecting Other Sugars to Glucose Metabolism

  • Glycogen, a polymer of glucose, is an energy-storage molecule in animals.

• Initiation of Transcription in Prokaryotes

  • The transcription initiation phase ends with the production of abortive transcripts, which are polymers of approximately 10 nucleotides that are made and released.

• Sporophytes and Gametophytes in Seedless Plants

  • The spores of seedless plants are surrounded by thick cell walls containing a tough polymer known as sporopollenin.

• Limits on Animal Size and Shape

  • As the tough and resistant outer cover of an arthropod, the exoskeleton may be constructed of a tough polymer, such as chitin, and is often biomineralized with materials, such as calcium carbonate.