It is used as a national identification number, tax payer number, social insurance number,driver's license number, for employment, etc. It is also commonly used as a customer number in banks, retailers, insurance companies, airlines, etc. Until the end of August 2013, the RUN was also used as the passport number.
The sclerenchyma cells are usually elongated, with tapering ends. Such cells are commonly described as sclerenchyma fibres. In some cases, the cells are shorter and irregular in shape. Such cells are commonly described as sclereids or stone cells.
1 Parenchyma tissues are made of simple, thin-walled cells. 2  In a carrot, for example, the parenchyma cells become a storage unit called the cortex. 3  In leaves, a layer of parenchyma tissues under the epidermis is active in photosynthesis. Epidermis is the single exterior layer that protects the stems, leaves, flowers, and roots. 2  The outside surface of the epidermis tissue is usually covered with a waxy substance called cutin, which reduces water loss. 3  Parenchyma tissues are made of simple, thin-walled cells.