B. Choose the letter of the correct answer The inner layer of the bone that contains yellowish substance which manufacture blood cells in the body a Skull b bone marrow c. hinge joint a spine column 2. There are total number of bones in mature human body a 306 b. 206 0 300 d. 200 3. The is a place where two bones meet a Cartilage b. marrow o ligament djoint 4. Bones that protects the heart and lungs. a. Skull b. pelvic bones orib cage d vertebral column 5. Bones that protects the spinal cord a. Skull b. pelvic bones crib cage d vertebral column