A&P Chapter 6 Flashcards
What does the human skeleton initially consist of?
Cartilage, which later is replaced by bone
What is skeletal cartilage made of?
Highly resilient, molded cartilage tissue that consists primarily of water. Contains no blood vessels or nerves
What is the perichondrium?
Layer of dense connective tissue surrounding cartilage
What does the perichondrum do?
Helps cartilage resist outward expansion, contains blood vessels for nutrient delivery to cartilage
What is cartilage made of?
Chondrocytes, cells encased in small cavities (lacunae) within jelly-like extracellular matrix
What are the three types of cartilage?
Hyaline, elastic, and fibrocartilage
What does hyaline cartilage provide?
Support, flexibility and resilience
Where is hyaline cartilage located?
Joints, ribs, respiratory, and nasal cartilage
What is elastic cartilage?
Similar to hyaline cartilage, but contains elastic fibers
Where is elastic cartilage located?
External ear and epiglottis
What is fibrocartilage made of?
Thick collagen fibers that has great tensile strength
Where is fibrocartilage located?
Menisci of knee, vertebral discs
What two ways does cartilage grow?
Appositional growth, and interstitial growth
What is appositional growth?
Thickness, cartilage-forming cells in perichondrium secrete matrix against external face of existing cartilage. A new matrix is laid down on surface on cartilage
What is interstitial growth?
Length, chondrocytes within lacunae divide and secrete a new matrix, expanding cartilage from within. A new matrix is made within cartilage.
What are the functions of bones?
- Support = For body and soft organs
- Protection = Protects brain, spinal cord, and vital organs
- Movement =Levers for muscle actions
- Mineral and growth factor storage = Calcium, phosphorous, and growth factors reservoir
- Blood cell formation = Hematopoiesis occurs in red marrow cavities of certain bones
- Triglyceride storage = Fat, used for an energy source, is stored in bone cavities
- Hormone production = Osteocalcin, which is secreted by bones helps to regulate insulin secretion, glucose levels, and metabolism
How many bones are in the human skeleton?
206
What are the two groups of bones that are based on location?
Axial skeleton, and appendicular skeleton
What is the axial skeleton?
Long axis of the body, contains the skull, vertebral column, and rib cage
What is the appendicular skeleton?
Limbs, shoulder, and hip
What are the classifications of bones by shape, and what is an example of each?
- Long bone (humerus)
- Flat bone (sternum)
- Irregular bone (vertebrae)
- Short bone (talus)
Is a bone an organ? Why or why not?
Yes, because they contain different types of tissues
What tissues do bones have?
Bone (osseous) tissue predominates, but a bone also has nervous tissue, cartilage, fibrous, connective tissue, muscle cells, and epithelial cells in its blood vessels
What are the three levels of bone structure?
Gross, microscopic, and chemical