the skin helps make what kind of vitamin?

what is a tough tight fitting membrane that covers the surface of bone?

what is a disease in which joints become irritated or inflamed?

what is a smooth slippery flexible tissue that cushions bone?

what is a place where two or more bones meet?

what is a strong tissue that connects bone to bone?

what is a bone disease that causes bone to weaken and become brittle?

what is an organ that can contract to move body parts?

what kind of muscle is found in the intestines, bladder, and blood vessels?

what kind of muscles are you able to control?

what kind of muscles are there that you can't control?

what kind of muscle is found only in the heart?

what are muscles that move bone?

what tissue attaches muscle to bone?

what kind of system includes hair, nails, and skin?

what is an injury to the skin where blood vessels are broken but the skin is not broken or open?

what is the outer layer of skin?

what is the pigment that protects your skin from sunlight and gives your skin color?

what is the layer of skin beneath the epidermis?