Final answer:
The spindle apparatus is broken down during telophase of mitosis.
Step-by-step explanation:
The spindle apparatus is broken down in telophase of mitosis. During telophase, the mitotic spindles are depolymerized into tubulin monomers, which will be used to assemble cytoskeletal components for each daughter cell. The chromosomes reach the opposite poles, nuclear envelopes form around them, and the chromatin starts to decondense.