Question

A colour blind woman marries a normal visioned male. In the offspring.
A. Both sons and daughter are color blind
B. All daughters are colour blind
C. All sons are normal
D. All sons are colour blind, daughters’ carriers

Answer 1

Color blindness is a familiar hereditary disorder that implies that your parents usually pass it down. Color blindness can simply be defined as a problem when colours such as blue, green, and red are seen or detected. There are some unusual instances where any colours cannot be seen and recognized by an individual at all.

Complete answer:
The 23rd chromosome consists of two elements. Either two X chromosomes if you are a woman, or if you are a man there will be an X, and a Y chromosome. Only on the X chromosome is the 'gene' that induces colour blindness. So, the color blindness 'gene' only has to appear on his X chromosome for a male to be colour blind. But It has to be present on both of her X chromosomes for a female to be colour blind.
She is regarded as a 'carrier' if a woman has only one color blind' gene. If she has a boy, she gives the child one of her X chromosomes. If she gives the X chromosome to her son with the color blindness gene, he will be color blind, but if he gets the X chromosome that does not hold the color blindness gene, he will not be color blind.
In the above scenario, since the mother is color blind, it means she has both affected X. So, all daughters will get one affected X from mother, and one normal X from father and will be a carrier. But all sons will get one affect X from mother and normal Y from father and will be color blind.

So, the correct answer is option (D).

Note: For regular color vision screening, the Ishihara Plate test is most widely used. In all eye clinics and schools, this is available. There are a total of 38 circle plates which are produced using two or more colours using irregular coloured dots. Patients are questioned to describe the number on a plate during the process of this diagnosis.