Answer:
I start with T end with T and within me is T.
What jumps when it walks, but sits when it stands?
I can wake you up in the morning but I require no electricity or winding.
You heard me before and then again. Afterward I die, until you call me again. What am I?
Lives in winter, dies in summer, and grows with its roots upward. What is it?
Whoever made me don't want me. Whoever bought me don't need me. Whoever use me don't know me.