Related Terms. Long-term (maturity over 10 years) fixed interest rate debt security issued by a national (federal) government backed by its 'full faith and credit.' Next to treasury bills (maturity less than one year), and treasury notes (maturity one to ten years) T-bonds are the safest form of marketable investment.
bacteria [pl. of bacterium], microscopic unicellular prokaryotic organisms characterized by the lack of a membrane-bound nucleus and membrane-bound organelles. Once considered a part of the plant kingdom, bacteria were eventually placed in a separate kingdom, Monera.
Types of Microorganisms. 1. Bacteria. Bacteria are unicellular organisms, about few microns in size (1 micron (Âµm) = 1/1,000 of a millimetre), consisting of DNA, cytoplasm, structures needed for metabolism and reproduction, cell membrane, cell wall and capsule (Picture 1). Certain bacteria use flagella, tail-like appendages, to propel themselves.