He was looking through a microscope at particles trapped in cavities inside pollen grains in water. The concept of Brownian motion is named after him. This is the random motion of particles suspended in a fluid, liquid or gas resulting from their collision with the fast-moving molecules. Here, the patterns of motion of the particles are typically alternations between random fluctuations in a particle's position inside a fluid sub-domain with a relocation to another sub-domain. Each relocation is followed by more fluctuations within the new closed volume.
In biology, the inner lining of tubular structures is called a lumen.
This can refer to numerous tubular structures in the body, such as the lumen of the veins and arteries, the lumen of the intestines or the tubes in the kidneys.
This term can also be used to describe a space defined by membranes of cell organelles such as the lumen of the mitochondria, the Golgi apparatus, and others.
Smooth er has less things inside of it and rough is more complex.
Polysaccharides are more difficult to digest then monosaccharides because they are much larger molecules.