According to one hypothesis, the hypertensive effect of alcohol is from a chronic state of alcohol withdrawal in frequent, heavy drinkers, but there is much evidence in favor of a direct effect of alcohol on BP.
Color Perception. The properties of color which are inherently distinguishable by the human eye are hue, saturation, and brightness. While we know that the spectral colors can be one-to-one correlated with light wavelength, the perception of light with multiple wavelengths is more complicated. It is found that many different combinations of light wavelengths can produce the same perception of color. This can be put in perspective with the CIE chromaticity diagram. The white or achromatic point E can also be achieved with many different mixtures of light, e.g. with complementary colors.
What is color blindness? Color blindness means that you have trouble seeing red, green, or blue or a mix of these colors. It's rare that a person sees no color at all. Color blindness is also called a color vision problem. A color vision problem can change your life. It may make it harder to learn and read, and you may not be able to have certain careers. But children and adults with color vision problems can learn to make up for their problems seeing color. What causes color blindness? Most color vision problems are inherited and are present at birth. People usually have three types of cone cells in the eye.