A layer of smooth cartilage at their ends, which cushions the bones and prevents them from rubbing directly against one another. The whole joint is also enclosed in a synovial capsule, which is full of synovial fluid. The synovial fluid acts like the oil in an engine, lubricating the joint and preventing the cartilage from becoming worn down.
There was less of it, making it more possible for the species to be extinct.
Answer:
The traits of a living thing depend on the complex mixture of interacting components inside it. Proteins do much of the chemical work inside cells, so they largely determine what those traits are. But those proteins owe their existence to the DNA (deoxyribonucleic acid), so that is where we must look for the answer
Explanation:
I'm not sure but I hope it's help