How does a substance cross the cell membrane in diffusion? a- flowing down the concentration gradient
b- binding to a carrier protein
c- going through a pump
d- going through a channel protein
(ck-12)

__1__ is a climate cycle where the temperature of the __2__ ocean changes because of movements of air and ocean currents. during this period, the trade winds in the south __3__ , causing the __4__ water to move from the __5__ region to the __6__ region. 1) el nino or the monsoon 2) atlantic, indian, or pacific 3) reverse, strengthen, or weaken 4) cold or warm 5) eastern or western 6) eastern or western

As the pea seeds respire, the level of coloured liquid in the left hand part of the capillary tube rises. by referring to what is happening in the apparatus, explain why the level of liquid changes

The “ecological footprint” left by a citizen of a developed nation is about four times larger than that left by a citizen of a developing nation. why is this the case?