In line 17, the quotation marks around the phrase “entertainment factor” imply that?

the indirect evidence that supports that the bubbles so generated are oxygen is that the bubbles in the plant increases when it moves towards the brighter light.

answer:

a possibility is  vasodilation.

"sweat  secretion stops when body temperature returns to normal. blood vessels supplying blood to the skin can swell or dilate - called  vasodilation."

"to maintain homeostasis, the blood vessels in your skin dilate to allow more blood flow to the surface of your body where it disperses the heat. you won’t feel the vasodilation, but you certainly will feel yourself sweating."

explanation: