1 . Complete the sentences using the correct form of the words and phrases below.

contain   electrical impulse   organ   locate   nerve   be responsible for   atom   relate to

1. The brain is the most important ________ in the human body.
2. It________ over one hundred billion ________ cells.
3. The nerve cells in our brain are connected by ________
4. There are more possible connections in one brain than there are ________ in the universe.
5. Different parts of our brain are ________ different parts of our body.
6. There are different areas in the brain that ________ different functions.
7. Scientists have ________ different areas of the brain.