They showed how organic molecules could be made from Earth's early atmosphere.
Their bodies taper to points at both the snout and the tail, reducing water resistance. Also decreasing drag -- and therefore noise -- are dermal denticles, sharp scales that cover the skin of most shark species. Rather than bone, sharks have cartilage, which is much lighter and more flexible. In addition, their livers produce squalene, a fatty oil that helps them remain afloat. Their pectoral fins allow them to quickly change direction, dive and swim upward.
http://animals.mom.me/unique-adaptations-sharks-survive-7845.html
Answer:
it uses it eye1s in the back of its head
Answer:
Cell membrane surround cells, but cell wall is an extra covering outside plant cells, made up of cellulose
