Example Of Essay On Glowing And Red Eyes

Everyone has taken a walk in the dark and has suddenly seen a pair of eyes watching and following them move. Also, at some point in time everybody has taken a picture and wondered why their eyes are red. Thus, the concept of glowing eyes is formed.
On the other hand, a similar phenomenon with glowing eyes can be seen in humans on pictures with flash. However, human eyes glow in red and only when the flash hits them in dark environments. The eye regulates how much light goes in by contracting or expanding the pupil, thus at night the pupils will expand. Yet, this makes the eyes unprepared for a sudden burst of light from a camera flesh. The color of the glow comes from the red blood vessels of the choroid which are revealed because the pupils are unable to contract fast enough when the flash hits them and thus the light reflects the red blood vessels, giving the eyes a red color (Yang, 2011).

Bibliography

"Why Do Animals Have Eyes That Glow In The Dark?" Companion Animal Hospital. 25 Jan. 2012. Web. 4 Apr. 2015. <http://cahvetclinics.com/why-do-animals-have-eyes-that-glow-in-the-dark>.
Seabrook, Andrea. "Why Do Animals' Eyes Glow In The Dark?" NPR. NPR, 31 Oct. 2008. Web. 4 Apr. 2015. <http://www.npr.org/templates/story/story.php?storyId=96414364>.
Yang, Bryan. "What Causes the Red Eye Effect?" Yale Scientific Magazine. 12 May 2011. Web. 4 Apr. 2015. <http://www.yalescientific.org/2011/05/what-causes-the-red-eye-effect/>.