This model shows the basic process of making a protein. What are the strengths and limitations of this model?

Alaska and northern canada have a diet rich in vitamin d and their skin color is darker than predicted on the basis of iv intensity at their latitude. explain the observation:

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.

Lymphatic vessels remove excess fluid from tissues. often after mammexront( the surgical procedure to remove of all or part of a breast) the lymphatic vessels draining the arm are damaged. explain a consequence of this damage. what can be done to reduce the symptoms?