Vertebrates developed about 550 million years ago. The oldest vertebrate fossils are those of FISH with no jaws. These e<span>arly jawless fish did not have paired fins and their bodies were covered with heavy, bony scaled, but their skeletons were made of cartilage. For the next 50 million years, they were the only vertebrates.</span>
Answer:
yes it is I have to write 20 letters but don't know What to put but yes it is apart of the cytoskeleton
I believe the answer is A.
I ruled out everything but C. and A. so it could be either.
Answer: Biodiversity is a measure of variation at the genetic, species, and ecosystem level.
Explanation: