Question

what is lumen and how is formed

Answer 1

Hlo mate...

here is your answer....

lumen formation is the delivery of membrane material to the apical plasma membrane of the lumen-forming cell, ....

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Answer 2

here is your answer...

The lumen is the SI derieved unit of luminous flux,a measure of the total quantity of visible light emitted by a source . Lumens are related to lux in that one lux is one lumen per square matter

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