Links DNA pieces together.

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:

Look at the picture below . what does this picture represent ?

Chlorophyll is found in plant leaves and absorbs light from the sun to enable plants to perform photosynthesis. magnesium is an important component of chlorophyll. the concentration of magnesium ions is higher in the root-hair cells of plants than in the soil. which mechanism of ion uptake would best enable a plant to produce a steady supply of chlorophyll? osmosis diffusion passive transport active transport