Assertion: size marker | /r/SimilarTo | the rungs of a ladder
Facets:
value: after separation
type: TEMPORAL
Source sentences:
text: For PAGE, some commercially available molecular weight markers (also called "ladders" because they look like the rungs of a ladder after separation) contain pre-stained proteins of different colours, so it is possible to determine more accurately where the proteins of interest in the samples might be.