On her first open-ocean dive in the Santa Barbara Channel, Widder says she dove down to 880 feet and turned off her lights. Explain why she did this and how she described what she saw?

She dove down to 880 feet and turned off her lights to observe bioluminescent animals in their natural habitat without visual obstruction from overhead lights. She saw many different animals of all shapes and sizes releasing bioluminescent light in different forms and variations.

the answer is d p: cell, q: organ, r: organ system, s: tissue

not always but somethings can be reproduced in a laboratory.