2.
Muscle tissue requires a great deal of ________________ to do its work.

3.
Proper _____________ is needed to keep muscles firm and strong.

4.
The main sources of energy in the diet are _______________ and ____________.

5.
_____________ type of muscles causes bones to move.

6.
_____________ muscle tissue composes the wall of the heart

7.
____________ muscles are found in the walls of internal organs and are involuntary muscles.