grana

(cell and molecular biology) A multilayered membrane unit formed by stacks of the lobes or branches of a chloroplast thylakoid.

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Hard dry grating cheeses such as parmesan.

[GRAH-nuh] Italian for "grain," referring to any of various very hard cheeses with a granular texture, like Parmigiano-Reggiano, which are particularly suited for grating. This special texture is the result of long aging, which is usually anywhere from 2 to 7 years, though some (rare) cheeses are ripened up to 20 years. See also cheese; parmesan cheese.