(a) This representation is of a normal person. In a normal person, the mRNA possesses the codon GAG which codes for the glutamic acid. (b) In the sufferer, the GAG is replaced by GUG in the mRNA which codes for valine. So, glutamic acid is replaced by valine during translation due to which RBC would be sickle-shaped. (c) The disease is sickle cell anemia which is an autosomal recessive trait.  Affected male in an autosomal recessive trait has to be homozygous recessive for defected allele i.e.HbS/HbS. Since both alleles are defected he can only transmit defected alleles to his children be it daughter or son. That is why both males and females will be equally affected.