Skeletal System Study Questions: Part 1
Answer all these questions in your journal.
1. What are the five main functions of the skeletal system?
a. Support
b. Protection
c. Movement
d. Resevoir for minerals and adipose
e. Hematopoiesis (red blood cell formation)
2. What are the 2 divisions of the skeletal system and their main functions? Describe these divisions in
regard to the bones they consist of.
a. Axial – protection and support – skull, vertebrae, thoracic cage
b. Appendicular – locomotion and manipulation of the environment – Arms, legs, shoulder girdle,
pelvic girdle
3. What are the 4 types of bones and give descriptions of each?
a. Long - longer than they are wide; bones of the limbs except for the (patella {kneecap} and the
bones of the wrist and ankle).
b. Short - Roughly cube shaped; Bones of the wrist and the ankle.
c. Flat - Thin, flattened, and usually a bit curved; Scapulae (shoulder blades), sternum, ribs and most
bones of the skull.
d. Irregular - Have weird shapes; Vertebrae, hip bones, 2 skull bones (sphenoid and the ethmoid
bones).
4. Besides bones, what other three organs are part of the skeletal system?
a. Ligaments
b. Tendons
c. Joints
5. Differentiate between the following three types of bone cells:
a. osteocytes – mature bone cells, maintaining the bone tissue
b. osteoblasts – bone building cells
c. osteoclasts – cells that digest bone matrix
6. Besides color, what is the difference between red and yellow marrow?
a. Red marrow – blood cell forming tissue = hematopoietic tissue
b. Yellow marrow – adipose tissue
7. Where is bone marrow located in each type of bone?
a. red marrow is limited to the axial skeleton, pectoral girdle, pelvic girdle, and proximal heads of the
humerus and the femur
b. yellow marrow is found in the medullary cavities of long bones in adults
Skeletal System Study Questions: Part 1
8. What are the structural units of compact bone?
Haversian systems/osteons
9. Differentiate between Haversian canals and Volkman’s canals.
a. Haversian canals are a central canal located in each osteon which allows the passage of blood
vessels, lymphatic vessels, and nerve fibers.
b. Volkman’s canals run perpendicular to the haversian canal and connect the blood and nerve supply in
the periosteum to those in the haversian canals and the medullary cavity.
10. Describe the function of each of the following terms:
a. canaliculi – hairlike canals that connect lacunae to each other and allow osteocytes to exchange
nutrients, waste, and chemical signals
b. lacunae – cavity surrounding the osteocytes
c. periosteum – double layered membrane surrounding bone richly supplied with nerve fibers,
lymphatic vessels and blood vessels
d. Sharpy’s fibers – collagen fibers that connect the periosteum to the bone
e. epiphyseal plate - growth plate near the ends of long bones where osteoblast activity increases bone
length
11. What percent of bone is organic and inorganic?
a. Organic – 1/3
b. Inorganic – 2/3
12. What are the inorganic substances that make up bone?
Mainly calcium phosphate and calcium hydroxide with smaller amounts of magnesium, fluoride, and
sodium
13. What is hematopoiesis and where does it occur?
Red blood cell formation and occurs in the red bone marrow
14. What is the difference between the diaphysis and the epiphysis?
a. Diaphysis – shaft on a long bone composed mainly of compact bone
b. Epiphysis – ends of long bones composed mainly of spongy bone
15. Where does primary ossification of bone take place?
Primary ossification begins in the center of the bone and continues proximally, distally, and laterally
16. Describe the steps in fracture healing?
Step 1 – hematoma formation
Step 2 – fibrocartilaginous formation
Step 3 – bony callus formation
Step 4 – bone remodeling
Skeletal System Study Questions: Part 1
17. Describe the function of the following 2 hormones in regard to resorption and remodeling of bone and
which cell types are stimulated by each: calcitonin and parathyroid hormone (PTH).