The correct answer is the amniotic egg. Hope this helps.
The water vascular system of a sea star enables movement, digestion and respiration through the use of water to exert force on limbs known as tube feet. The vascular system is primarily water but also contains coelomocytes, protein and potassium salts.
It’s actually bacterial DNA
I think it’s a, hopefully you get it right!
Arthritis is a term that is initially used to describe inflammation of the joints. Cartilage is a type of body tissue that keeps joints moving freely and functional well, and when they begin to break down or get inflamed, the joints don’t work as well, and it becomes painful to move