The Human Machine: Mystery 3

Front

What happens to your pupil when the room goes dark?

Back

It opens wider to allow in more light.

Front

Why do people sometimes have red eyes in photos taken with a flash?

Back

The camera's flash lights up the blood vessels at the back of the eye.

Front

What do the pupils of nocturnal animals do to let in more light?

Back

They open really wide.

Front

When would you want your pupils to open wide?

Back

In a dark room.

Front

What are you seeing when you notice 'red eye' in a human photo?

Back

The blood vessels in the retina.

Front

What is the function of the pupil in low light conditions?

Back

To allow more light to enter the eye.

Front

What is the biological reason for red-eye effect in photography?

Back

The flash reflects off the blood vessels in the retina.

Front

How do pupils adjust in response to light intensity?

Back

They constrict in bright light and dilate in low light.

Front

What is the role of the retina in vision?

Back

It converts light into neural signals for the brain.

Front

What is the significance of pupil dilation in animals?

Back

It enhances their ability to see in low light conditions.