Single function switches are the most commonly used adaptive switches. This type of switch performs one function (i.e., on/off) this switch has only one function - on or off. The switch may only be in one of the states at any one moment in time. Multiple function switches may perform two or more functions.
Echinocytes and keratocytes should be considered in the differential diagnosis of spur cell anemia. Echinocytes or burr cells are spiculated red blood cells with uniform, narrow, spikelike surface projections. Spur cells have fewer spicules, and the spicules vary more in size than echinocytes. Keratocytes are acanthocytelike cells with bizarre shapes and horny projections. Differential Diagnoses.
Collenchyma cells are elongated cells with irregularly thick cell walls that provide support and structure. Their thick cell walls are composed of the compounds cellulose and pectin. These cells are often found under the epidermis, or the outer layer of cells in young stems and in leaf veins.