This would make both of his parents Dd genetypes.
Bob's sister could either not have the disease at all, DD, or be a carrier, Dd. If she was a carrier she then poses the chance of passing the disease on through child birth. Her father was unaffected, which means he must have been DD, which would make his mother probably Dd, so the chances are equal of Bob's sister being either DD, or Dd, with a fifty percent chance of being either of the genotypes.
Both DNA and RNA are made up of different tiny particles of information, often referred to as nucleotides. The nucleotides of Adenine, Guanine, Cytosine, and Thymine all make up DNA. In RNA however, Thymine is displaced and Uracil takes its place. It is these four proteins which help make up the coding and information of our bodies. Various proteins can then used these nucleotides, and based on the order they are in, read the information stored there. For example, the order of these nucleotides varies from species to species, and is always different for members of one species to members of another species.
The DNA is copied into RNA, which is almost identical to the original coding of the DNA. ...