The classification into epithelial organs, connective tissues, and the more specialized muscle and nerve, was largely due to him; and he proved the presence of neuroglia in the brain and spinal cord, discovered crystalline haematoidine, and made out the structure of the umbilical cord.
People specialized, technology advanced, and as a result, men walked on the moon.
He specialized in them.
Highly specialized air-sacs are characteristic of all birds.
Highly specialized experts are a few keystrokes away and can be hired for just a few minutes or hours at a time.