The skin's dermis is made of layers of cells, connective tissue and several structures that aid in maintaining its function. These structures include blood vessels, hair follicles, lymph vessels and glands.
XnY one color blind boy. 1  Probability of having a color blind daughter is (1/2 x 1/2) or 1/4 or 25% (0.25) This is because both sex and colorblindness are involved in the solution.  The probability that their first son is color blind is 50% (0.50). In this question only males are part of the solution.
Question: I have a three yr old son who I think may be colorblind. It runs in my husband's family. My problem is that most vision tests have numbers that you are supposed to recognize to determine if you are color blind or not. My son, however, is not old enough to know what a number is.