The fossil record provides evidence of Earth’s changes over time. It's a record keeper of the Earth'd changes over time.
IL-2 is one of many cytokines that govern the immune response. It acts as a mitogen for T cells, potentially enhancing their proliferation and activity, improving antigen generation, and raising the synthesis and release of other cytokines.
Osmosis only talks about water molecules
Diffusion talks everything other then the water molecules.
So,
Osmosis : water molecules travel from a region of a higher water potential to a region of lower water potential through a partially permeable membrane via osmosis
Diffusion : Travels from a region of higher concentration to a region of lower concentration through a partially permeable membrane via diffusion
Answer:
Because it is a solid that has trapped air with the water molecules in cold temperature thus creating a hard solid.