Assertion: chloroplast's structure | /r/CapableOf | remain murky
Facets:
value: until fibrous material
type: TEMPORAL
value: until chloroplasts ribosomes
type: TEMPORAL
Source sentences:
text: However, the structure of chloroplasts remained murky until the discovery of the electron microscope in the mid-20th century which allowed researchers to describe individual membranes, chloroplasts ribosomes, fibrous material identified as DNA and other discrete structures (Hoober 1990).