What extends from the base of the brain to almost the lower end of the back bone?

What is the coloured circle in the eye called?

Some of our actions are automatic, we do not have to think before doing them, these actions are called:

We can feel the sensation of touch, heat, pain or pressure because of our:

What is protected by a hard bony skull?

What forms the outermost covering of our body?

What looks like a black spot?

There are many nerve endings in the upper part of our:

Which is the largest sense organ?

Which of the following needs a continuous supply of blood and oxygen?