Muscles need much more energy. Mitochondria are the powerhouse of the cell and produces all of the ATP that a cell needs. The more mitochondria there is, the more energy that is produced
A change in which no new substance is formed is called a physical change.
Examples: Crushing a can, Melting an ice cube, Boiling water, Breaking glass, Dissolving sugar in water, Shredding paper, and Chopping wood.
All of these examples may involve a change in shape, form, or appearance, but it DOES NOT involve a change in the molecule structure.
