Body Systems and Homeostasis

2. The outer superficial layer of skin is the ____.
6. ______ found in many other bones, consists of stored fat.
7. _____ is a pigment that absorbs light energy, which protects deeper cells from the damaging effects of ultraviolet rays of sunlight.
10. The outer layers of epidermal cells contain ____.
11. The involuntary muscle present only in the heart is called ________.
15. The formation of bone from osteblasts is called _______.
16. Red and white blood cells and platelets are produced in ________.
17. ______ are muscles attached to bones by tendons and when tightened, or contracted, cause movement.
18. Cells called ______ break down bone cells, which are then replaced by new bone tissue.
19. Directly beneath the epidermis is the _____.
20. The _____ includes the bones of the shoulder, arms, hands, hips, legs and feet.

1. Hair cells grow out of narrow cavities in the dermis called ______.
3. As the name suggests _____ is less dense and has many cavities that contain bone marrow.
4. _____ is dense and strong; it provides strength and protection.
5. ______ lubricate skin and hair.
8. The ____ includes the skull, the vertebral column, the ribs,and the sternum.
9. ______ are tough bands of connective tissue that attach one bone to another.
12. Many hollow internal organs such as the stomach, intestines, bladder, and uterus are lined with _____.
13. The blood vessles provide oxygen and nutrients to ____ -- living blood cells.
14. During fetal developement, cells in fetal cartilage develope into bone-forming cells called _____.