Which of the following doesn't have a specific, internal, crystalline structure or a specific, predictable chemical composition? lab-grown gemstone
seashells
smoky quartz
Obsidian

Which blood cell spend most of their time in the lymphatic system?

Astudent sees several ants walking up a wall following the exact same trail that an ant took earlier. she wants to apply the scientific method to determine how the ants detected the trail. which of these steps would come first in her application of the scientific method? perform an experiment by cleaning the scent away from part of the trail. draw a conclusion that the ants follow a scent trail. make a prediction about what the ants will do after she cleans away part of the trail. hypothesize that the ants are following a scent trail that the first ant left.

Darwin’s studies of finches on the galápagos islands suggest that the finches’ differences in beak structure were most likely directly due to: