Question

Color blindness is due to defect in
a. Cones
b. Rods
c. Rods and cones
d. None of the above

Answer 1

Hint: There are two types of cells in the retina of eyes. Rods are the photo Rey cells that contain rhodopsin pigment linked with the scotopic vision of the eyes. Iodopsin, porpyrosin cyan opsin pigments contained from the cones. The genetic disorders that are obtained in the cones are known as color blindness that arise on the X chromosome and known as X linked recessive disorder.

Complete answer:
Color blindness is a defect that arises in the eyes that makes it difficult for a person to distinguish between or among colors. Color blindness is a genetic disorder that is obtained in the female on the both X chromosomes and only one X chromosome affected in the male. Some drugs such as sildenafil, erythromycin and antidiabetic also cause the color blindness.

The symptoms of color blindness are people unable to distinguish red or green color but sometimes not able to see yellow color. But some people are only able to see gray and black color because of the disorder. Vanishing plate, pseudo isochromatic plate test, transformation plate and Ishihara test used to detect the color blindness. Some parameters on the human eyes used to distinguish color but not in the identification of the color. But currently no treatment available for the color blindness.

Hence, the correct answer is option (A).

Note: In the vertebrate eyes including the human eye cone cells act as photoreceptor cells present in the retina. And respond differently to light of different wavelengths and also provide the function of relatively bright light, and work better in the dim light or also responsible for the color vision of the eyes.