Which of the following is a possible scenario that could lead to a new species?

The gene that causes sickle-cell disease is present in a higher percentage of residents of sub-saharan africa than among those of african descent living in the united states. even though this gene causes sickle-cell disease, it also provides some protection from malaria, a serious disease that is widespread in sub-saharan africa but absent in the united states. discuss an evolutionary process that could account for the different percentages of the sickle-cell gene among residents of the two regions.

Drag each label to the correct location on the image. each label can be used more than once. a scientist introduced mutations in a gene sequence isolated from bacteria. study the sequence, and identify the steps where the mutations may affect the formation of proteins. in the sequence, black letters stand for protein coding regions and red letters stand for noncoding regions. protein will not be changed. protein may be changed. attcgtgttc atcgtgttc atcgtattc attcgtattc

During sunny hours, a large amount of build up between the hours of 1: 00-5: 00 pm. a. ozone b. mercury c. lead d. sulfuric acid