| Imagine that a young boy (whose bones are still growing) has snapped his femur in half. A small portion of the bone is protruding from his skin. When the doctor examines this fracture, what part of the bone will not be visible (i.e., will not be protruding from the skin)? | 
  |  |    |  | All of these structures will be visible. |   |  | the marrow cavity and bone marrow |   |  | spongy bone |   |  | the diaphysis |   |  | compact bone |  | 
  
  
    | 7. | The hormone oxytocin stimulates contraction of: | 
  |  |    |  | the smooth muscles in the walls of blood vessels. |   |  | skeletal muscles. |   |  | the muscles of the stomach wall. |   |  | uterine muscles. |  | 
  
  
    | 8. | When muscles combine to produce similar motions at a joint, they are called: | 
  |  |    |  | antagonists. |   |  | agonists. |   |  | isometric. |   |  | flexors. |   |  | extensors. |  | 
  
  
    | 9. | A ball-and-socket joint: | 
  |  |    |  | has fewer muscles controlling it than a hinge joint. |   |  | has a greater range of motion than a hinge joint. |   |  | is less likely to become dislocated than a hinge joint. |   |  | All of these choices are correct. |  | 
  
  
    | 10. | The hydroxyapatite that makes up the bulk of the bony endoskeleton of vertebrates is found in: | 
  |  |    |  | the collagen. |   |  | osteoblasts. |   |  | osteocytes. |   |  | the extracellular matrix surrounding osteocytes. |  | 
  
  
  
  
  
       | Imagine that a young boy (whose bones are still  growing) has snapped his femur in half. A small portion of the bone  is protruding from his skin. When the doctor examines this  fracture, what part of the bone will not be visible (i.e., will not  be protruding from the skin)? | 
    |  |       |  | All of these structures  will be visible. |    |  | the marrow cavity and  bone marrow |    |  | spongy bone |    |  | the diaphysis |    |  | compact bone |  | 
    
Ans 6 c spongy bone
 Spongy or the cancellous bone is present at the ends of long bones called as epiphysis so that will not be exposed during the injury