Light travels in _________________ lines.

Light enters the eye through the ______.

When it is bright, the pupils in your eyes get ___________.

We see objects when light __________ them.

You should wear _____________ to protect your eyes from the Sun.

What is an animals with a backbone called?

If an animal has a skeleton on the inside of their body, we say it has what type of skeleton? 

What type of skeleton does an elephant have?

The spine is another word for the _____ 

Which of the below has the function of protecting your lungs and heart?