The function of the iris is to control light levels in the eye. The round, black dot in the center of the iris is called the pupil.Know More
The iris is the barrier between the front and back of the eye. Each iris has a muscle running through it that constricts and dilates to allow the right amount of light to enter the eye at any given time. The sphincter muscle lies around the edge of the pupil. In bright light, this muscle contracts, allowing only a small amount of light to get it. In dim light, the sphincter muscle dilates, letting in as much light as possible.
Each person's texture, color and pattern of the iris is unique and the color of the irises come from a pigment called melanin. Eye color comes from the amount of melanin a person produces in black/brown or red/yellow combinations.
Like other parts of the body, the iris may become diseased or infected. When the iris becomes inflamed, the result may be blurred vision and light sensitivity. Iridocyclitis is a condition in which the iris requires antibiotics to function normally. Congenital problems of the iris such as, iris coloboma and aniridia are rare and require seeking professional medical treatment.Learn more about Organs
According to the American Optometric Association, the eye works by light entering the eye and traveling through the different parts of the eye. Each part plays a vital role in creating a visual image.Full Answer >
The gallbladder's function is to store bile produced by the liver and release the bile into the small intestine during digestion in order to neutralize acids and break down fats. The fat in the digested food enters the small intestine, releasing cholecystokinin and triggering the gallbladder to release bile via the common bile duct.Full Answer >
Villi are microscopic, slender, hair-like projections that line the small intestine to facilitate food absorption, explains Encyclopædia Britannica. Villi number between 6,000 and 25,000 per square inch of the small intestine, with greater densities near the beginning of the organ closer to the stomach. Villi are also found in the placenta surrounding a fetus in the womb.Full Answer >
Glomeruli are the components that carry out the primary filtering action of the kidney. They connect on one side to the blood vessels that enter the kidney, and on the other side to fluid-collecting structures called tubules. The glomeruli accept the blood from the arteries and pass the filtered wastes and any extra water present into the tubules, according to the National Institute of Diabetes and Digestive and Kidney Diseases.Full Answer >