1. The Skeletal System
Section 32.2

2. Structure of the Skeletal System
Consists of two divisions.
The axial skeleton: skull, vertebral column, the ribs, and the sternum.
The appendicular skeleton: bones of the shoulders, arms, hands, hips, legs, and feet.

3. Major Bones of the Skeletal System

4. Compact and Spongy Bone
The outer layers of all bones are composed of compact bone.
Spongy bone is found at the center of short or flat bones and at the end of long bones.

5. Bone Marrow Two types: Red: Produces red, white blood cells Yellow:
Consists of stored fat.

6. Formation of Bone
During fetal development, cells in fetal cartilage develop into bone-forming cells called osteoblasts.
Osteoblasts are the cells responsible for the growth and repair of bones.

7. Remodeling of Bone
Bones constantly are being remodeled, which involves replacing old cells with new cells.
Cells called osteoclasts break down bone cells, which are replaced by new bone tissue.

8. Repair of Bone
Simple Fracture:
Bone breaks, but does not come through the skin
Compound fracture
Bone protrudes through the skin.
Stress fracture
Thin crack in the bone.

9. Fracture Repair:
1. A blood clot forms between the broken ends of the bone
2. New bone begins to form.
3. Soft callus of cartilage forms at the location of the break.

10. Callus Formation
4. Osteoblasts form a callus made of spongy bone that surrounds the fracture.
5. Osteoclasts remove the spongy bone while osteoblasts produce stronger, compact bone.

11. Remodeling Bones require different amounts of time to heal.
Age, nutrition, location, and severity of the break are all factors.

12. Joints
Occur where two or more bones meet.
Held together by ligaments.

16. Osteoarthritis
A painful condition that affects joints and results in the deterioration of the cartilage
Rheumatoid Arthritis
Affected joints lose strength and function and are inflamed, swollen, and painful.
Bursitis
Inflammation of the bursa sac, a membranous sac surrounding a joint that contains lubricating fluid
Sprains
A tear in a ligament

17. Functions of the Skeletal System
Support for the body
Act as a point of attachment for muscles to allow movement.
Provides protection for organs and bone marrow.
Bones are reservoirs for the storage of minerals, such as calcium and phosphorus.

18. What are the living bone cells?
Chapter Diagnostic Questions
What are the living bone cells?
osteoclasts
osteocytes
cartilage
bone marrow

19. Wrists and ankles have which type of joint?
Chapter Diagnostic Questions
Wrists and ankles have which type of joint?
hinge
pivot
gliding
ball-and-socket

20. Which division of the skeleton is related to the movement of limbs?
32.2 Formative Questions
Which division of the skeleton is related to
the movement of limbs?
axial skeleton
appendicular skeleton

21. What type of tissue is bone?
connective tissue
epithelial tissue
integumentary tissue
ligamentary tissue

22. Where in this bone is the spongy bone tissue?
32.2 Formative Questions
Where in this bone is the spongy bone
tissue?

23. Where in the bone is fat stored?
32.2 Formative Questions
Where in the bone is fat stored?
osteons
spongy bone
bone marrow
Haversian canals

24. What results from damage to the ligaments that hold joints together?
32.2 Formative Questions
What results from damage to the ligaments
that hold joints together?
bursitis
tendonitis
osteoarthritis
a sprain

25. What is the function of osteoclasts?
They break down bone cells.
They produce blood cells and platelets.
They are responsible for growth and repair
of bones.
They form a callus of cartilage at the
location of a break.

26. What cells produce spongy bone at the site of this fracture?
osteoblasts
osteocytes
periostium cells
red marrow cells

27. What causes bursitis?
Cartilage in moveable joints deteriorates.
Fluid-filled sacs surrounding joints
become inflamed.
Joints lose strength and function and
become swollen.
Ligaments that hold joints together
become overstretched.

28. What is one way that bones help the body
maintain homeostasis?
They are constantly being remodeled.
They provide divisions of movement.
They provide framework for the skin.
They store and release calcium.

29. Which joint provides the widest range
of motion?