Bones and skeletal tissues Flashcards
What is perichondrium
Dense connective tissue girdle that contains blood vessels for nutrient delivery to cartilage
What is hyaline cartilage
Provide support, flexibility, and resilience
What is elastic cartilage
similar to hyaline, but contain elastic fibers
what is fibrocartilage
collagen fibers with great tensile strength and it absorbs compressive shock
What is appositional growth of cartilage
Cells secrete matrix against the external face of existing cartilage, increase of diameter
What is interstitial growth of cartilage
Chondrocytes divide and secrete new matrix, expanding cartilage from within, increase of length
What are the 7 functions of bones
Support, protection, storage, blood cell formation, triglyceride storage, and hormone production
What is compact bone
Dense outer layer
What is spongy bone
Also known as trabecular bone, it is a honeycomb for trabeculae and has open spaces filled with bone marrow
What is a diaphysis (shaft)
Compact bone collar surrounding medullary (marrow) cavity, which in adults contains fat (yellow marrow)
What is epiphyses
Expanded ends, spongy bone interior, epiphyseal line, and articular (hyaline) cartilage on joint surfaces
What is periosteum membrane
- the outer fibrous layer (mostly osteogenic cells that give rise to all bone cells except bone destroying cells)
- Nerve fibers, nutrient blood vessels, and lymphatic vessels enter the bone via nutrient foramina
- Secured to underlying bone by perforating fibers
What is endosteum
- Delicate membrane on internal surfaces of bone
- Contains osteogenic cells
What is the structure of short, irregular, and flat bones
- Periosteum covered compact bone on the outside
- Endosteum covered spongy bone within
- Spongy bone called diploë in flat bones
- bone marrow between the trabeculae
What is hematopoietic tissue
red bone marrow
Describe bone cavities in adults vs infants
In adults trabecular cavities are in the heads of the femur and humerus as well as the diploë in flat bones. In infants medullary cavities and all spaces in spongy bone
What are the cells of the bone
Osteogenic cells, osteoblasts, osteocytes, osteoclasts, and bone-lining cells
What are osteogenic cells
Stem cells in periosteum and endosteum that give rise to osteoblasts and bone lining cells. Develops into an osteoblast basically
What are osteoblasts
Bone forming cells that secrete bone matrix and are responsible for bone growth
What are osteocytes
Mature bones cells, maintain matrix
What are osteoclasts
Cells that break down (resorb) bone matrix
What are bone-lining cells
They’re found on bone surfaces not being remodeled. They look like stem cells, act like osteocytes
What is an osteon of compact bone
A structural unit, it’s the cylinder vascular tunnel that contains the lamella, central canal, perforating canal, lacunae, and canaliculi
What is the lamellae
Weight bearing column like matrix tubes
What is the central canal
Contains the blood vessels and nerves in the osteon
What are the perforating canals
They are at right angles to the central canal, and connects blood vessels and nerves of the periosteum and the central canal
What is the lacunae
Small cavities that contain osteocytes
What is a canaliculi
A hairlike canal that connect lacunae to each other and the central canal. They’re the little things coming off of the lacunae