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 ...
Ad. The timpani is another type of pitched percussion instrument. Also called the kettle drum, timpani are bowl shaped drums which have a skin stretched over the top. The skin is struck with a large, soft mallet, and the bowl causes the sound to reverberate. Typically, an orchestra has three or four timpani drums.lthough not typically used in orchestras, steel drums are also a type of pitched percussion. A percussion instrument is any instrument that is struck to produce a sound. The piano actually uses felt lined hammers to strike the strings to create a sound.