A farm pond, usually dry during winter, has plenty of water and aquatic pond life during the summer. One summer, Sarah returns to the family farm from college. Observing the pond, she is fascinated by some six-legged organisms that can crawl about on submerged surfaces or, when disturbed, seemingly "jet" through the water. Watching further, she is able to conclude that the "mystery organisms" are ambush predators, and their prey includes everything from insects to small fish and tadpoles.
-Sarah observed that the mystery pond organisms never come up to the pond's surface. If she catches one of these organisms and observes closely, perhaps dissecting the organism, she should find
A) gills.
B) spiracles.
C) tracheae.
D) book lungs.

Question

Quizplus · Accepted Answer

The correct answer is A) gills because the organisms live underwater and do not come up to the surface, indicating they breathe underwater, which is a function of gills. Spiracles, tracheae, and book lungs are associated with air-breathing organisms.

A Farm Pond, Usually Dry During Winter, Has Plenty of Water