Cellular component

GO:0045279

NADH dehydrogenase (ubiquinone) complex, NADH dehydrogenase complex (ubiquinone), NADH-Q oxidoreductase complex

Respiratory chain complex I is an enzyme of the respiratory chain. It consists of several polypeptide chains and is L-shaped, with a horizontal arm lying in the membrane and a vertical arm that projects into the matrix. The electrons of NADH enter the chain at this complex.

electron transport complex I

Note that this term represents a location and not a function; the activity possessed by this complex is mentioned in the definition for the purpose of describing and distinguishing the complex. The function possessed by this complex is represented by the molecular function term 'NADH dehydrogenase (ubiquinone) activity ; GO:0008137'.