Light Pollution and Its Effects

1.Light pollution occurs when ___ from human sources brightens the night sky.

2.Extra light comes from street lights, buildings, cars, and ___.

3.In cities and towns, the sky often looks ___ at night instead of dark.

4.The main cause of light pollution is ___ that points upward or sideways.

5.Street lights often send light in ___ instead of just down to the ground.

6.All of this light goes up into the sky and creates a ___ over cities.

7.Many birds travel long distances at night using ___ to find their way.

8.When the sky is too bright, birds become confused and fly into ___.

9.Baby turtles use ___ to find the ocean after they are born.

10.Moths and other night insects are attracted to ___.

11.Insects fly around street lights for hours instead of looking for food or ___.

12.This behaviour makes insects ___ for animals that hunt them.

13.___ are falling in areas with high levels of light pollution.

14.The human body uses darkness as a signal to produce a chemical called ___.

15.Melatonin helps people feel sleepy and controls the body's natural ___.

16.When people are exposed to bright light at night, their bodies make ___.

17.Cities can use better street lights that point downward and have ___ on top.

18.Using ___ helps because lights only turn on when someone is nearby.

19.Choosing ___ instead of bright white lights also helps reduce light pollution.

20.More than one hundred ___ now exist around the world.