Final answer:
Lisa and Monica are the carriers for red-green color blindness. This is due to the X-linked recessive inheritance pattern of the disorder, which allows females to be carriers without expressing the trait.
Step-by-step explanation:
The individuals in the pedigree who are identified and labeled carriers for red-green color blindness are Lisa and Monica. This is because red-green color blindness is an X-linked recessive disorder. Affected males have the condition because they possess only one X chromosome, and if that X chromosome carries the gene for colorblindness, they will exhibit the trait. Females, on the other hand, have two X chromosomes and can be carriers if they inherit one affected X chromosome and one normal X chromosome. In this case, the dominant normal gene masks the recessive colorblind gene, so the trait is not expressed, but they can still pass it on to their offspring.
Males cannot be carriers of red-green color blindness, unlike what some statements imply; they are either affected or unaffected. This is due to males having only one X chromosome. A son affected by red-green color blindness must have inherited the affected X chromosome from his mother. When analyzing pedigrees for X-linked recessive disorders like red-green color blindness, one would expect to see affected males much more frequently than females, as affected females would require two copies of the affected gene, one from each parent.
Learn more about carriers of red-green color blindness here: