Final answer:
MTOCs, particularly the B. centrosome with its centrioles, are found near the nuclei of animal cells. They organize microtubules during cell division, with kinetochore microtubules connecting to kinetochores on centromeres to segregate chromosomes.
Step-by-step explanation:
MTOCs, or microtubule-organizing centers, are critical structures in the cell that play a role in organizing the microtubules during cell division. One of the most well-known MTOCs is the centrosome, which is found near the nuclei of animal cells and contains a pair of centrioles. These centrioles are instrumental in the formation of the mitotic spindle. The mitotic spindle forms from the centrosomes and is responsible for separating chromosomes during cell division. During the late prophase, or 'prometaphase,' the nuclear membrane dissolves, allowing the mitotic spindle to invade the nuclear area and attach itself to the kinetochores located on the centromeres of sister chromatids. There are two types of microtubules involved: non-kinetochore microtubules and kinetochore microtubules. The latter specifically attach to kinetochores and play a direct role in chromosome movement.
MTOCs, or Microtubule Organizing Centers, are found at the centromeres (and kinetochores if present) as well as at the centrioles. During mitosis, a mitotic spindle forms from the centrosomes, and the nuclear envelope dissolves. Chromosomes attach to the mitotic spindle, which separates the chromosomes and elongates the cell.