Diffusion is the movement of particles from a high concentration area to a low concentration area.
Things that can go through a membrane are ions (charged), small polar molecules. Big molecules can't go through the membrane due to its large size and disrupting the membrane.
Passive transport is the movement of substances acrpss the cell membrane w/o the use of energy. Active transport needs energy to move substances across a cell membrane.
The fibrous proteins which are found in connective tissues of the animals are either collagen, elastic, or reticular fibers. This collagen fibers provide strengths to the connective tissues.
Hope this helps
Non polar has a symmetry. Polar has no symmetry. You can tell from shape.
