It can be either diffusion, osmosis or active transport. depending on what is transported and how in which net direction they're moving.
Answer:
c lower oxygen levels
Explanation:
the higher up the person is the closer to the atmosphere so there is less oxygen
Soil structure is important becuse it does affect the characteristic of soil.
this is how particles are arrange in different type of soil
Sand soil:particles are very loose,it does not rentent water or nutrients,lack humus
clay soil:very packed particles,becomes water logg,rich in nutrient and humus.but is not aerated
Loamy soil is not packed in particles but is kind of in between
