Prophase and Prometaphase

 

1. Prophase

   • Chromosomes condense.

   • Spindle fibers begin to form from the centrioles (in animal cells).

   • Centrioles start moving toward opposite poles of the cell.

2. Prometaphase (sometimes taught as late prophase)

   • The nuclear envelope fully breaks down.

   • Spindle fibers grow longer and attach to chromosomes at the kinetochores.

So:

• Prophase → spindle fibers start growing.

• Prometaphase → spindle fibers connect to chromosomes.