1 In the cytoplasm, the mitotic spindle, consisting of microtubules and other proteins, forms between the two pairs of centrioles as they migrate to opposite poles of the cell. 2  The nuclear envelope disappears at the end of prophase. 3  This signals the beginning of the substage called prometaphase.
  Percussion Family. The Timpani is struck by mallets ... any instrument that requires a percussive touch is a member of this family ...surprisingly enough, and a little â¦ known fact, the Piano is also a member of the Percussion Family ... a key must be struck to produce a tone!!5 people found this useful.he Timpani is struck by mallets ... any instrument that requires a percussive touch is a member of this family ...
They are struck with felt tipped wooden sticks. Timpani were the first drums to be used in the orchestra, joining the ensemble over 300 years ago. Timpani are a tuned instrument and produce a specific pitch that is determined by the drum's size.Most orchestras use three or four timpani of varying sizes. The pitch is fine-tuned by tightening the drumhead with keys and foot pedals.impani are a tuned instrument and produce a specific pitch that is determined by the drum's size. Most orchestras use three or four timpani of varying sizes. The pitch is fine-tuned by tightening the drumhead with keys and foot pedals.