Weather changes every day, while climate changes annually or every 3 months
Cell transport is useful because it's, essentially, the movement of cells across the blood/veins. Active transport uses energy, while passive transport does not.
It's an Agrarian society, hope this helps!
Acetylene (C2H2) has a triple bond between the two carbons. So 3 pairs of electrons. Biomed is talking about ethylene (C2H4).