Cholesterol acts as the precursor to steroid molecules many of which function as hormones.
Capillaries are the smallest of all blood vessels.
A trait acquired during an organisms life span cannot be passed down through it's genetic lineage.
Answer:
adenosine triphosphate (ATP)
Explanation:
Active transport mechanisms require the use of the cell's energy, usually in the form of adenosine triphosphate (ATP).
Clams are adapted for burrowing in the mud and sand by having a short siphon (tube that intakes water) that allows them to expel mud and sand from their gils. They also have adapted by using their foot to dig down into the sand. The foot pushes down through the media and then the clam can pull it self down to the tip of their foot.