Which of the following defects are usually inherited? (Choose 2)

Protanopia and deuteranopia are both color vision deficiencies that are typically inherited in a sex-linked recessive manner, often associated with the X chromosome. Protanopia is characterized by an inability to perceive red light properly due to a lack of functional long-wavelength cones. Similarly, deuteranopia involves a deficiency in medium-wavelength cones, leading to difficulty in distinguishing between greens and other colors.

Both conditions are more commonly found in males, as they have only one X chromosome. If a male inherits the defective allele from his mother, he will express the condition. Females, having two X chromosomes, would need to inherit two copies of the defective allele (one on each X chromosome) to express these color vision deficiencies.

In contrast, tritanopia and achromatopsia do not follow the same inheritance patterns. Tritanopia, which affects the perception of blue light, is a rare condition and is not sex-linked, making it less likely to be inherited in the same way as protanopia and deuteranopia. Achromatopsia, a condition characterized by total color blindness, can result from various genetic mutations and may exhibit different inheritance mechanisms, including autosomal recessive patterns.

Thus, the correct options