2. Pertaining to a person or a thing that is readily able to assume different characters or forms: The protean nature of the friendly ghost in the house was baffling, sometimes appearing like a puppy and other times like a wisp of smoke.
The food guide issued by the health department included a list of protean ways to get protein in people's diets without necessarily eating lots of meat.
Proteins are required for the structure, function, and regulation of the body's cells, tissues, and organs. Each protein has unique functions. Proteins are essential components of muscles, skin, bones and the body as a whole.
Examples of proteins include whole classes of important molecules, among them enzymes, hormones, and antibodies.
Protein is one of the three types of nutrients used as energy sources by the body, the other two being carbohydrate and fat. Proteins and carbohydrates each provide four calories of energy per gram, while fats produce nine calories per gram.
The word "protein" was introduced into science by the great Swedish physician and chemist, Jöns Jacob Berzelius (1779-1848), who also determined the atomic and molecular weights of thousands of substances, discovered several elements including selenium, first isolated silicon and titanium, and created the present system of writing chemical symbols and reactions.
Etymology: from French protéine, from Greek proteios, "the first quality"; from protos, "first". Originally a theoretical substance thought to be essential to life, the modern use is from German Protein, borrowed in English about 1907.
They are transported via the portal vein to the liver and then into the general circulation and to the tissues.
Each tissue synthesizes its own form of protein from the amino acids received from the blood.
They are found primarily in connective tissue and cartilage.
2. Any of a group of glycoproteins in connective-body tissue, made of carbohydrates and protein.They serve as binding or cementing materials for body tissues.
From the angles and intensities of these scattered beams, a crystallographer can produce a three-dimensional picture of the density of electrons within the crystal.