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Individuals who suffer from sicke cell anemia have deformed erythrocytes. The parasite that causes malaria(plasmodium malarie) uses erythrocytes for reproduction and as part of the infection. Those parasites can't infect sickle erythrocytes. It supports evolution by natural selection because individuals who had sickle cell couldn't get malaria so they lived long enough to have offspring and pass on their genes(including sickle cell). Individuals who didn't have sickle cell died of malaria and didn't get to have offspring. That's why sickle cell has a high frequency in the continent of Africa where malaria is also frequent.
It will be an Rr I just did answer on quiz
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
A eukaryotic cell is much more complex than a prokaryotic cell. Eukaryotic cells usually make up more complex organisms and have organelles such as endoplasmic reticulum, Golgi apparatus, mitochondria, a nucleus, and lysosomes. A prokaryotic cell only has circular chromosomes and is much smaller than a eukaryotic cell. Most single celled organisms are prokaryotes.
