# I am part of your body

I am part of your body.
Without my head, I can live in the forest.
Without my tail, I will be something a ball can do.
And without my head and my tail, You must remember me.

What am I?

I think it is

SPINE

Without my head, I can live in the forest.

PINE

Without my tail, I will be something a ball can do.

SPIN

And without my head and my tail, You must remember me.

PIN

I am part of your body.

THROAT

Without my head, I can live in the forest.

OAT — Wild oats could grow in a sparse forest

Without my tail, I will be something a ball can do.

THRO (or throw) — A ball is often made to be thrown

And without my head and my tail, You must remember me.

O (or oh) — Mirriam-Webster's 3rd definition of "oh" is "used to express acknowledgment or understanding of a statement". The example they provide is "Oh, yes. It's one of my favorite cities." Doesn't seem like too much of a stretch...