Mass of the molecules diffusing: Heavier molecules move more slowly; therefore, they diffuse more slowly. The reverse is true for lighter molecules. ... Because cells primarily use diffusion to move materials within the cytoplasm, any increase in the cytoplasm's density will inhibit the movement of the materials.
As the density of a solvent increases, the rate of diffusion decreases. The molecules slow down because they have a more difficult time getting through the denser medium. If the medium is less dense, diffusion increases.
The answer is sympathetic. It is one of two components of the
autonomic nervous system; the other being parasympathetic. The other function of
the sympathetic system is to maintain body homeostasis. Acetylcholine
is the main neurotransmitter in the preganglionic
sympathetic neurons while noradrenaline (norepinephrine) is the main neurotransmitter
in the postganglionic sympathetic neurons.
The constant motion of particles in a gas allows a gas to fill a container of any shape or size. Particles in a gas are in constant, random motion. The motion of one particle is unaffected by the motion of other particles unless the particles collide.