T and B cells. Lymphocytes originate from stem cells in the bone marrow; these stem cells divide continuously, releasing immature lymphocytes into the bloodstream. Some of these cells travel to the thymus, where they multiply and differentiate into T lymphocytes, or T cells.
Cellophane is a thin, transparent sheet made of regenerated cellulose. Its low permeability to air, oils, greases, bacteria and water makes it useful for food packaging. Cellophane is in many countries a registered trade mark of Innovia Films Ltd based in Wigton, Cumbria, United Kingdom.
A cello is a large stringed instrument, related to the viola, violin, double bass, and bass violin. The name cello is a shortening of violoncello, and is sometimes written with an apostrophe as âcello. The cello is usually played with a bow, as the violin, although it may also be plucked. The earliest origins of the cello date back to the mid-16th century, when a three-stringed bass violin was created. For the next hundred years a number of pieces were composed for this instrument, which was usually meant to be played in concert with a violin. In the mid-17th century, with the advent of metal-wrapped strings, an instrument much more like the modern cello was created.