12. What function SPECIFICALLY causes oxygen to diffuse into blood, and CO2 to diffuse
into alveoli?
A. Blood carries oxygen to the lungs and CO2 away from the lungs.
B. Air in the alveoli has a greater concentration of oxygen, and lower concentration of CO2
than the blood in the lungs.
C. Blood passes into capillaries that supply body cells with oxygen, and pick up CO2 as cell
waste.
D. The heart pumps blood to the lungs

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.