Questions: Why was sickle-cell more likely to persist in Africa as opposed to another area, like the North Pole? Because sickle-cell causes everyone who has it to get malaria. Because almost no one lives in the North Pole. Because gene mutations happen more often in Africa than in other parts of the world. Because the environment in Africa was filled with malaria-causing mosquitos, which meant people carrying one sickle cell gene were more likely than non-carriers to live long enough to make babies because the sickle gene gave them relative protection against a deadly disease.

Why was sickle-cell more likely to persist in Africa as opposed to another area, like the North Pole?
Because sickle-cell causes everyone who has it to get malaria.
Because almost no one lives in the North Pole.
Because gene mutations happen more often in Africa than in other parts of the world.
Because the environment in Africa was filled with malaria-causing mosquitos, which meant people carrying one sickle cell gene were more likely than non-carriers to live long enough to make babies because the sickle gene gave them relative protection against a deadly disease.

Transcript text: Why was sickle-cell more likely to persist in Africa as opposed to another area, like the North Pole? Because sickle-cell causes everyone who has it to get malaria. Because almost no one lives in the North Pole. Because gene mutations happen more often in Africa than in other parts of the world. Because the environment in Africa was filled with malaria-causing mosquitos, which meant people carrying one sickle cell gene were more likely than non-carriers to live long enough to make babies because the sickle gene gave them relative protection against a deadly disease.

Solution

The answer is the last one: Because the environment in Africa was filled with malaria-causing mosquitos, which meant people carrying one sickle cell gene were more likely than non-carriers to live long enough to make babies because the sickle gene gave them relative protection against a deadly disease.

Explanation for each option:

Because sickle-cell causes everyone who has it to get malaria.
This statement is incorrect. Sickle-cell disease does not cause malaria; rather, carrying one sickle cell gene (sickle cell trait) provides some protection against malaria, which is why the trait persists in malaria-endemic regions.
Because almost no one lives in the North Pole.
While it is true that the North Pole is sparsely populated, this is not the reason why sickle-cell is more prevalent in Africa. The prevalence is linked to the selective advantage provided by the sickle cell trait in malaria-endemic regions.
Because gene mutations happen more often in Africa than in other parts of the world.
This statement is misleading. While genetic diversity is high in Africa, the persistence of the sickle cell trait is specifically due to the selective pressure exerted by malaria, not a higher mutation rate.
Because the environment in Africa was filled with malaria-causing mosquitos, which meant people carrying one sickle cell gene were more likely than non-carriers to live long enough to make babies because the sickle gene gave them relative protection against a deadly disease.
This is the correct explanation. The sickle cell trait provides a survival advantage in regions where malaria is prevalent, allowing carriers to have a better chance of surviving and reproducing, thus passing on the gene to future generations.

In summary, the sickle cell trait persists in Africa due to the selective advantage it provides against malaria, which is prevalent in the region.

Was this solution helpful?