Answer:
Since sickle cell disease is a disorder with an autosomal dominant inheritance pattern, and in light of the lack of data, it could be said that the only way for Pat and Tracy to have a child with sickle cell disease is for both of them to be healthy carriers of the gene, with a 25% probability.
Explanation:
Considering that both Pat and Tracy each have a sibling with a sickle cell trait and that both they and their parents are healthy, it must be assumed that some of their parents are healthy carriers:
- Pat and Tracy do not have sickle cell trait. In this case, there is no chance that they will have a child with sickle cell disease.
- Either Pat or Tracy has the trait, but the other does not. It is possible that at least one of their children is a healthy carrier.
- If both Tracy and Pat have sickle cell trait, the chances of having a child with sickle cell disease are:
Alelles R r
R RR Rr
r Rr rr
RR: healthy (25%).
Rr: healthy carrier (50%).
rr: sickle cell disease (25%).
<em>If Pat and Tracy are healthy carriers of the gene that determines sickle cell disease, the chance of having a child with the disease is 25%</em>.
Learn more:
Autosomal recesive inheritance brainly.com/question/10605612
B
Vaccinations protect people when they are exposed to the microorganism to which they were vaccinated. This secondary response happens when the person is exposed to the microorganism. At that time, IgG production is a lot higher, making it the main antibody class in the second response. IgM is more active when it comes to the first exposure. A lot of people who have allergies have IgE in their bodies, too. IgA is the most common secretory antibody, and it stops pathogens from attaching and invading through the mucosal membranes of the body.
..............4 is D and 6 is A
