About one-third of the retail trade industries â $7.5 million in average annual receipts. A few, such as grocery stores, department stores, motor vehicle dealers (except new car dealers) and electrical appliance dealers have a higher size standard, ranging from $11 million to $38.5 million in average annual receipts.
spindle fibers. Spindle fibers form a protein structure that divides the genetic material in a cell. The spindle is necessary to equally divide the chromosomes in a parental cell into two daughter cells during both types of nuclear division: mitosis and meiosis. During mitosis, the spindle fibers are called the mitotic spindle.
Spindle fibers are a part of the spindle apparatus, which moves chromosomes during mitosis and meiosis to ensure each daughter cell gets the correct number of chromosomes. The spindle apparatus consists of spindle fibers, motor proteins, chromosomes, and in some cells, structures called asters. In animal cells, spindle fibers are produced from cylindrical microtubules called centrioles. Centrioles form asters and asters generate spindle fibers during the cell cycle. Centrioles are located in a region of the cell known as the centrosome. Spindle Fibers and Chromosome Movement