<span>Assuming that this is referring to the same list of options that was posted before with this question, it is the "sun" that is inexhaustible. Of course technically even the sun will burn out someday, but that won't happen for billions of years. </span>
An animal that is healthier will have a better chance of survival due to better strength, and also be better suited to winning a mate. Animals that are weak or sick are most likely to die off or be killed by a predator or natural reasons, if this animal survives, it will most likely not get a mate because the mate will not be attracted to the sickened animal, considering how most animals search for a healthy mate to reproduce with. (Usually there is some type of court ship dance or song of some sort, and it is usually the more healthy animal that is able to "perform" the best dance/song for the mate it is trying to win over) Hope that this helped!
<span>Cell membrane is comprised of phospholipids (its major component ) which can create lipid bilayers because of their water attracting characteristics. Another lipid inside the cell membrane is </span>cholesterol, <span>which makes the cell membrane more fluid. Cholesterol is a waxy fat-like substance found in all cells of the body. </span>
<span>When you have a high cholesterol, it can create a plaque in your arteries thus, develop a high risk of heart disease. People who have high cholesterol has a greater possibility to acquire coronary heart diseases.</span>
They need lots of lift to fly (so like wind) and they need to go at a certain speed to maintain flying.
