Sex linkage and color blindness are discussed. Color blindness is a genetic condition where individuals have difficulty distinguishing between certain colors, particularly red and green. It is caused by genes on the X chromosome, so it occurs more often in males. There are several types of color blindness depending on which cone is affected - protanopia affects red cones, deuteranopia affects green cones, and tritanopia affects blue cones. Color blindness is detected using charts with colored dots arranged in patterns that color blind individuals see differently. Effects include problems distinguishing colors and difficulties in activities like cooking, gardening, sports and driving.