In cell biology, spindle apparatus refers to the subcellular structure that segregates chromosomes between daughter cells during cell division. It is also referred to as the mitotic spindle during mitosis or the meiotic spindle during meiosis.
While the spindle apparatus is composed of hundreds upon hundreds of proteins, the fundamental machinery are the spindle microtubules. Attachment of microtubules to chromosomes is mediated by kinetochores, which actively monitor spindle formation and prevent premature anaphase onset. Microtubule polymerization and depolymerization dynamics drive chromosome congression. Depolymerization of microtubules generates tension at kinetochores; bipolar attachment of sister kinetochores to microtubules emanating from opposite cell poles couples opposing tension forces, aligning chromosomes at the cell equator and poising them for segregation to daughter cells. Once every chromosome is bi-oriented, anaphase commences and cohesin, which couples sister chromatids, is severed, permitting the transit of the sister chromatids to opposite poles.
Fritz Künkel (September 6, 1889 - April 2, 1956) was known both as a German psychiatrist and an American psychologist. He might best be understood as a social scientist who sought to integrate psychology (especially the work of Freud, Adler and Jung), sociology and religion into a unified theory of human being. He consolidated these insights into a theory of character development and finally into his "We-Psychology".
The following material comes from the brief life written by John A. Sanford with the assistance of Kunkel's two sons.