Answer:
6. B.
7. D.
8. C
9. D
10. C
Explanation:
6. Hinge joint is a convex surface of one bone that fits into concave surface of another bone. This allow a limit movement sin one plane only, like back and forth. Some example of bones with hinge joints are: elbow and the joints in phalanges.
7. The skull protects the brain and forms the shape of the face. The spinal cord, a pathway for messages between the brain and the body, is protected by the backbone, or spinal column.
8. Cilia are hair-like projections that move microbes and debris up and out of the airways. The mucus layer traps pathogens (potentially infectious microorganisms) and other particles, preventing them from reaching the lungs.
9. The biceps and triceps muscles work together to allow you to bend and straighten your elbow. When you want to bend your elbow, your biceps muscle contracts (Figure below), and, at the same time, the triceps muscle relaxes. The biceps is the flexor, and the triceps is the extensor of your elbow joint.
10. . As blood passes through the lungs, oxygen is being picked up by oxygen moves from the alveoli to the blood through the capillaries (tiny blood vessels) lining the alveolar walls. Once in the bloodstream, oxygen gets picked up by the hemoglobin in red blood cells.
