Advantages <span>sexually by releasing sperm and eggs into the water, forming a planula the bad part is its babys can get eaten and hurt easily </span>
Well, an endoskeleton is an internal skeleton, like humans have.
Pro: Bones do not get broke as easily, since they are inside of the body. Bones that break also heal more quickly in an endoskeleton, since they have tissue and blood surrounding it and transferring nutrients.
Con: The flesh can get easily damaged. There is no shedding with endoskeletons, so a new skeleton cannot be grown in the event of an injury.
An explanation of how the natural world works.
Filtered blood leaves the kidney through the renal vein and flows back to the heart. Pee leaves the kidneys and travels through the ureters to the bladder. The bladder expands as it fills.
Answer:
The membrane that covers the lungs is called the pleura :)
Explanation: