The human iris contains two muscles that control pupil size, allowing it to change aperture in approximately 1 second to regulate light entering the eye; in low light, the iris opens to allow more light to reach the retina, while in bright light, it closes to protect the eye. The iris is composed of smooth muscle tissue, which enables rapid adjustments. Some individuals experience temporary iris color changes when excited or tired due to increased muscle activity. The iris plays a crucial role in maintaining clear vision, and its examination can help detect certain health conditions such as diabetes or high blood pressure.
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👁️ THE HUMAN EYE'S IRIS #ShortsAdded:
Iris changes aperture in 1 second. The iris has two muscles. They control the pupil size. This changes how much light enters the eye. In low light, the iris opens up. This lets more light hit the retina. In bright light, it closes to protect the eye. The iris is made of smooth muscle. It can change the pupil size fast. This happens in less than a second. Some people have irises that change color. This can happen when they are excited or tired. It's because the iris muscles are active. The iris controls how much light enters the eye.
This is important for clear vision.
Without it, we would be blinded by light or unable to see in the dark. Some animals have vertical irises. This helps them see better in the dark. Their irises can open very wide to let in more light. Understanding the iris is important for eye health. Doctors can use iris scans to detect some diseases.
The iris can show signs of diabetes or high blood pressure.
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