Untitled Flashcards Set

Here’s a structured version with questions and answers side by side:

Skeletal System Overview

1. What are the functions of the skeletal system, and how are they accomplished?

• Support – Provides framework (e.g., vertebral column, rib cage).

• Protection – Shields organs (e.g., skull protects brain, ribs protect heart/lungs).

• Movement – Works with muscles (bones act as levers).

• Mineral Storage – Stores calcium/phosphate, releases when needed.

• Blood Cell Production (Hematopoiesis) – Red marrow produces blood cells.

• Fat Storage – Yellow marrow stores fat as an energy reserve.

• Hormone Production – Produces osteocalcin (regulates bone formation & metabolism).

2. What are the two divisions of the skeletal system, and what bones make up each?

• Axial Skeleton (80 bones) – Skull, vertebral column, thoracic cage, hyoid.

• Appendicular Skeleton (126 bones) – Pectoral girdle, upper limbs, pelvic girdle, lower limbs.

3. What are the two types of bone marrow, their makeup, functions, and locations?

• Red Marrow – Produces blood cells; found in flat bones & ends of long bones.

• Yellow Marrow – Stores fat; found in medullary cavity of long bones.

4. What are the cellular components of bone tissue, their functions, and how do they change with age?

• Osteoblasts – Build bone.

• Osteocytes – Maintain bone.

• Osteoclasts – Break down bone for remodeling & calcium release.

• Bone Matrix: Organic (collagen – flexibility) & Inorganic (calcium phosphate – hardness).

• Changes Over Life Stages:

  • Pre-adolescence – Osteoblasts dominate.

  • Adulthood – Balance of osteoblasts & osteoclasts.

  • Old Age – Osteoclasts dominate, leading to bone loss.

5. How do compact and spongy bone differ in structure and function? Where are interstitial and circumferential lamellae located?

• Compact Bone – Dense, strong; contains osteons with central canals for blood supply.

  • Interstitial lamellae (between osteons), circumferential lamellae (outer bone surface).

• Spongy Bone – Porous, lighter; contains trabeculae, supports marrow & resists stress.

6. What are the layers of the periosteum and endosteum, and what are their functions?

• Periosteum – Outer fibrous layer (protection) & inner cellular layer (osteoblasts).

• Endosteum – Lines medullary cavity; contains osteogenic cells for growth/remodeling.

7. What are the two types of bone development, and how do they differ?

• Endochondral Ossification – Cartilage replaced by bone (long bones).

• Intramembranous Ossification – Bone forms from connective tissue (skull, clavicle).

8. What is appositional bone growth, and how do we know when it has ended?

• Process – Increases thickness by adding layers to periosteum.

• Ends When – Epiphyseal plates close, seen as epiphyseal line in adults.

9. What is bone remodeling, and what is its purpose?

• Continuous replacement – Balances osteoblast & osteoclast activity.

• Responds to stress – Strengthens bone based on mechanical load.

10. What are the major blood vessels that service bones, and where are they located?

• Nutrient arteries – Enter via nutrient foramen; supply bone marrow.

• Periosteal arteries – Supply outer bone layers.

• Metaphyseal & Epiphyseal arteries – Supply growth regions.

11. What are the different bone shape classifications and examples of each?

• Long Bones – Humerus, femur.

• Short Bones – Carpals, tarsals.

• Flat Bones – Skull, ribs, sternum.

• Irregular Bones – Vertebrae, pelvis.

• Sesamoid Bones – Patella.

12. Where are the paranasal sinuses located, and what are their functions?

• Frontal – Above eyes; lightens skull.

• Maxillary – Below eyes; largest, drains nasal cavity.

• Ethmoid – Between eyes; supports nasal structure.

• Sphenoid – Behind ethmoid; helps with resonance.

13. Where are the nasal conchae located, and what are their functions?

• Superior & Middle (Ethmoid bone) – Filters & warms air.

• Inferior (separate bone) – Enhances airflow efficiency.

14. What bones make up the zygomatic arch, hard palate, nasal septum, and orbital complex?

• Zygomatic Arch – Zygomatic & temporal bones.

• Hard Palate – Maxilla & palatine bones.

• Nasal Septum – Vomer & perpendicular plate of ethmoid.

• Orbital Complex – Frontal, sphenoid, zygomatic, maxilla, palatine, ethmoid, lacrimal.

15. What are the regions of the vertebral column, and how many vertebrae are in each?

• Cervical (7)

• Thoracic (12)

• Lumbar (5)

• Sacrum (5, fused)

• Coccyx (4, fused)

16. What are the spinal curves of the vertebral column?

• Primary (born with) – Thoracic, Sacral.

• Secondary (develop later) – Cervical (lifting head), Lumbar (walking).

17. What is the thoracic cage composed of, and how do ribs connect to the sternum?

• Sternum – Manubrium, body, xiphoid process.

• Ribs (12 pairs):

  • True (1-7) – Attach directly to sternum.

  • False (8-10) – Attach indirectly.

  • Floating (11-12) – No attachment.

18. What bones make up the pectoral and pelvic girdles?

• Pectoral Girdle – Clavicle & scapula.

• Pelvic Girdle – Ilium, ischium, pubis.

19. What bones make up the pelvis, and how is it adapted for pregnancy? How does the male pelvis differ from the female pelvis?

• Bones – Ilium, ischium, pubis.

• Female Adaptations – Wider inlet, shallower, larger pubic angle.

• Male Differences – Narrower, deeper pelvis.

20. What are the greater and lesser pelvis, and what are their boundaries?

• Greater (False Pelvis) – Above pelvic brim; supports intestines.

• Lesser (True Pelvis) – Below pelvic brim; encloses pelvic organs.

21. What are the pelvic inlet and outlet, and what are their boundaries?

• Pelvic Inlet – Superior opening; baby enters birth canal.

• Pelvic Outlet – Inferior opening; baby exits during birth.