If you are a woman of childbearing age, you should take to support a healthy pregnancy. this also to prevent neural tube defects.

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.

Type the correct answer in the box. use numerals instead of words. fiona has a lovely flower bed in her yard. she wants to add a fence along one side of the flower bed. the fence material is sold in meters. fiona knows that her flower bed is 200 centimeters in length. how much fencing material does fiona need in meters? fiona needs meters of fencing material for her flower bed.

Explain why phospholipid molecules form a bilayer. (3 marks)