GreatExplorations

Name: ______________________   Date: ____________

Use the clues to fill in the crossword.

Across

  1. 1. That part of the central nervous system that includes all the higher nervous centers (5)
  2. 2. A small flat triangular bone in front of the knee that protects the knee joint (7)
  3. 5. The outer and thinner of the two bones of the human leg between the knee and ankle (6)
  4. 9. Either of two saclike respiratory organs in the chest of vertebrates (4)
  5. 11. A mechanical device in a camera that controls size of aperture of the lens (9)
  6. 13. A blood vessel that carries blood from the heart to the body (6)
  7. 14. The longest and thickest bone of the human skeleton (5)
  8. 15. A blood vessel that carries blood from the capillaries toward the heart (4)

Down

  1. 1. Rigid connective tissue that makes up the skeleton of vertebrates (4)
  2. 3. One of the tubules forming the respiratory system of most insects and many arachnids (7)
  3. 4. Large and complicated reddish-brown glandular organ located in the upper right portion of (5)
  4. 6. A large elongated exocrine gland located behind the stomach (8)
  5. 7. One of the contractile organs of the body (6)
  6. 8. The region of the body of a vertebrate between the thorax and the pelvis (7)
  7. 10. The length of a line segment between the center and circumference of a circle or sphere (6)
  8. 12. The structure of the vertebrate skeleton supporting the lower limbs in humans and the hind limbs (6)