Exam 3 Study Guide: Skeletal System, Bones, and Joints (Ch. 6–8)

Q1. What is the difference between appositional and interstitial bone growth?

Background

Topic: Bone Growth and Development

This question tests your understanding of the two main ways bones grow in size and thickness during development and throughout life.

Key Terms

• Appositional Growth: Growth in the diameter or thickness of bones.

• Interstitial Growth: Growth in the length of bones, typically at the epiphyseal plate.

Step-by-Step Guidance

1. Recall that appositional growth involves the addition of new bone tissue at the surface of existing bones, increasing their thickness.

2. Remember that interstitial growth occurs within the cartilage of the epiphyseal plate, leading to an increase in bone length.

3. Think about which cell types are involved in each process (e.g., osteoblasts for appositional growth, chondrocytes for interstitial growth).

4. Consider when each type of growth is most active (e.g., childhood, adolescence, or adulthood).

Try explaining the differences in your own words before checking the answer!

Q2. What is the anatomy and physiology of the periosteum and endosteum?

Background

Topic: Bone Structure

This question focuses on the layers that cover and line bones, and their roles in bone health and remodeling.

Key Terms

• Periosteum: A dense connective tissue membrane covering the outer surface of bones.

• Endosteum: A thin membrane lining the internal surfaces of bones, including the medullary cavity.

Step-by-Step Guidance

1. Identify the location of the periosteum (external bone surface) and endosteum (internal bone surfaces).

2. List the main functions of each (e.g., bone growth, repair, nutrient supply).

3. Recall the types of cells found in each layer (e.g., osteoblasts, osteoclasts, osteoprogenitor cells).

4. Think about how these structures contribute to bone remodeling and healing.

Try to outline the anatomy and functions before revealing the answer!

Q3. What are the effects of different hormones on bone physiology?

Background

Topic: Hormonal Regulation of Bone

This question examines how hormones like parathyroid hormone, calcitonin, and sex hormones influence bone growth and remodeling.

Key Terms

• Parathyroid Hormone (PTH): Increases blood calcium by stimulating bone resorption.

• Calcitonin: Lowers blood calcium by inhibiting bone resorption.

• Growth Hormone, Sex Hormones (Estrogen/Testosterone): Stimulate bone growth and maintenance.

Step-by-Step Guidance

1. List the main hormones involved in bone physiology.

2. Describe the effect of each hormone on bone cells (osteoblasts and osteoclasts).

3. Explain how these hormones help regulate blood calcium levels and bone density.

4. Consider how hormone imbalances might affect bone health (e.g., osteoporosis).

Try to match each hormone to its effect before checking the answer!

Q4. What are the different types of bone cells and their functions?

Background

Topic: Bone Histology

This question tests your knowledge of the cellular components of bone tissue and their roles in bone maintenance and remodeling.

Key Terms

• Osteoblasts: Bone-forming cells.

• Osteocytes: Mature bone cells that maintain bone tissue.

• Osteoclasts: Bone-resorbing cells.

• Osteoprogenitor Cells: Stem cells that differentiate into osteoblasts.

Step-by-Step Guidance

1. List each type of bone cell and where it is found in bone tissue.

2. Describe the primary function of each cell type.

3. Explain how these cells interact during bone remodeling.

4. Think about what happens if one cell type is overactive or underactive.

Try to recall the function of each cell before revealing the answer!

Q5. What are the steps in endochondral ossification?

Background

Topic: Bone Development

This question focuses on the process by which most bones form from a cartilage template during fetal development and childhood.

Key Terms

• Endochondral Ossification: The process of bone formation from hyaline cartilage models.

• Primary Ossification Center: The first area of bone formation, usually in the diaphysis.

• Secondary Ossification Centers: Areas of bone formation in the epiphyses.

Step-by-Step Guidance

1. Recall that the process begins with a hyaline cartilage model of the bone.

2. Describe how the cartilage calcifies and is replaced by bone tissue in the diaphysis (primary ossification center).

3. Explain the development of secondary ossification centers in the epiphyses.

4. Consider the role of the epiphyseal plate in continued bone growth.

Try to list the steps in order before checking the answer!

Q6. What are the functions of the skeletal system?

Background

Topic: Skeletal System Overview

This question asks you to summarize the major roles the skeletal system plays in the human body.

Key Terms

• Support

• Protection

• Movement

• Mineral Storage

• Blood Cell Production (Hematopoiesis)

• Triglyceride Storage

Step-by-Step Guidance

1. List each function of the skeletal system.

2. Provide a brief explanation or example for each function (e.g., "protection"—the skull protects the brain).

3. Think about how the skeletal system interacts with other body systems (e.g., muscular, circulatory).

Try to write out the functions before revealing the answer!

Q7. Which three bones fuse together to form the pelvis?

Background

Topic: Pelvic Girdle Anatomy

This question tests your knowledge of the bones that make up the pelvic girdle and how they fuse during development.

Key Terms

• Ilium

• Ischium

• Pubis

Step-by-Step Guidance

1. Recall the names of the three bones that form each hip bone (coxal bone).

2. Think about where these bones are located and how they contribute to the structure of the pelvis.

3. Consider at what age these bones typically fuse.

Try to name all three bones before checking the answer!

Q8. Which bone in the lower extremity is not weight bearing?

Background

Topic: Lower Limb Anatomy

This question asks you to identify the bone in the leg that does not support body weight during standing or walking.

Key Terms

• Tibia: Main weight-bearing bone of the lower leg.

• Fibula: Lateral bone of the lower leg, not weight bearing.

Step-by-Step Guidance

1. Recall the two bones in the lower leg and their positions (medial vs. lateral).

2. Think about which bone forms the main support for the body’s weight.

3. Identify the bone that provides muscle attachment but does not bear weight.

Try to identify the non-weight-bearing bone before revealing the answer!

Q9. What are the different abnormal curvatures of the spine?

Background

Topic: Vertebral Column Anatomy

This question tests your knowledge of common spinal deformities and their characteristics.

Key Terms

• Scoliosis: Lateral curvature of the spine.

• Kyphosis: Exaggerated thoracic curvature (hunchback).

• Lordosis: Exaggerated lumbar curvature (swayback).

Step-by-Step Guidance

1. List the three main types of abnormal spinal curvatures.

2. Describe the direction and region of the spine affected by each curvature.

3. Think about possible causes or risk factors for each abnormality.

Try to match each curvature to its description before checking the answer!