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typically exists as a twisted double strand, i.e. a double helix. Deoxyribose has one less

oxygen atom than ribose, making it more stable. The double helix protects the genetic

information and allows repair via the opposite strand. Both lead to the fact that DNA stores

information much better than RNA.

Domain Name Server  Specific number (IP address), e.g. 132.187.25.1, of a computer

via which it is connected to the Internet protocol.

Dotplot  Allows to compare two sequences in a diagram (x-/y-axis) to find similar areas

(represented as a dot).

Drug Design  A branch of bioinformatics that deals with the design of a drug with opti­

mal properties.

Dynamic Programming  Systematic trying of possibilities for optimizing solutions with

the computer, such as secondary structure folding, dynamically allocating more and more

memory. 

Elementary Mode Analysis  Part of metabolic modelling/metabolic modelling in which

all metabolic sources, metabolic product/excretions (“sinks”) as well as involved enzymes,

metabolites (internal/external) and metabolic reactions (reversible/irreversible) are trans­

lated into a mathematical calculation rule. It is calculated which enzyme chains (metabolic

pathways) each put all internal metabolites involved into equilibrium (elemental flux

modes). Elementary mode analysis is important, for example, in order to achieve the best

possible yield of a product (sinks) with a starting product (sources) or to identify differ­

ences between organisms, for example, with regard to medical use (e.g. antibiotic that

blocks metabolic pathways of the bacterium but does not cause a toxic effect in the patient). 

Emergence  System effect in which new effects and properties arise from the coming

together of the components that cannot be attributed to the individual components, e.g.

individual blood and heart muscle cells form the circulatory system with properties such

as blood pressure and pulse.

ENCODE (ENCyclopedia of DNA Elements)  The ENCODE project (consortium) is

the follow-up project to the Human Genome Project (sequencing of the human genome)

and seeks to characterize the entire human genome and transcriptome in greater functional

detail. 

Endosymbionts, Endosymbiont Hypothesis  Large organelles, especially mitochondria

and chloroplasts, also contain DNA and a small ring-shaped DNA molecule (a few thou­

sand nucleotides). This indicates descent from free-living bacteria (endosymbiont

hypothesis). 

Enzyme  see Protein. 

18  Glossary