Bone Tissue Lecture Notes

These flashcards cover the key vocabulary and concepts from the lecture on bone tissue, including definitions and functions of various types of bone cells, processes of bone development and remodeling, and classifications of fractures.

Osseous Tissue

Connective tissue with the matrix hardened by calcium phosphate and other minerals. contains cells, fibers, and ground substance

Osteology

The study of bones.

Types of Bone

Bone is classified into long, short, flat, irregular, and sesamoid bones.

Hematopoiesis

The formation of blood cells, which occurs in the red marrow of certain bones.

Osteoblasts

Bone-forming cells that synthesize bone matrix.

Osteoclasts

Bone-dissolving cells that resorb bone.

Bone Matrix Composition

Bone matrix is composed of 1/3 organic (collagen and protein) and 2/3 inorganic (minerals like hydroxyapatite and calcium).

Compact Bone

Dense outer layer of bone that appears smooth and solid.

Spongy Bone

Bone made up of a honeycomb of small, needle-like or flat pieces called trabeculae.

Intramembranous Ossification

The process of bone development in flat bones that forms bone from fibrous membranes.

Endochondral Ossification

Process in which bone replaces hyaline cartilage; forms most of the skeleton.

Parathyroid Hormone (PTH)

Hormone released in response to low blood calcium levels that raises calcium levels.

Hypocalcemia

Condition of having deficient calcium in the blood.

Fractures

Breaks in the bone classified by structural characteristics such as direction of fracture line.

Osteocytes

Former osteoblasts that maintain bone tissue, residing in lacunae.

Bone Remodeling

The process through which bone is continually renewed throughout life.

Bone Healing Stages

The stages include hematoma formation, soft callus formation, hard callus formation, and bone remodeling.

Living tissue is made of ?

dynamic tissues, Full of cells, Permeated with nerves and blood vessels

what are the skeletal functions?

Support, protection, movement, mineral and growth factor storage, blood cell formation, Triglycerides (fat) storage, and hormone production.

What is Osteocalcin?

helps regulate insulin secretion, glucose levels. and metabolism.

What is a flat bone?

Consist of thin plates of spongy bone covered by compact bone

Compact bone sandwiched between

connective tissue membranes

Periosteum covers the

outside of the compact bone

Bone marrow is scattered throughout

spongy bone

Hyaline cartilage covers an area of bone

a movable joint

Diaphysis

a tubular shaft that forms the long axis of the bone

Epiphyses

ends of long bones that consist of compact bone externally and spongy bone internally

medullary cavity

is filled with yellow bone barrow

Articular cartilage

covers articular joint surfaces

Bone surrounded by membrane and

Dense regular connective tissue, collagen fibers, Periosteum (surrounding the bone) Endosteum (within the bone)

Osteons

function unit of bone

lamellae

layers of bone tissue, Concentric, Circumferential,Interstitial

Concentric lamellae

Surrounds a center canal running longtitude

Circumferential lamellae

fill out outer region of dense bone

Interstitial lamellae

fill irregular regions between osteons

Central Canal on Compact bones

Runs through a core of osteon, contains blood vessels and nerve fibers

perforating canals

canal lines filled with endosteum that happen at right angles, connects blood vessels, nerves of periosteum, medullary cavity and central canal.

Canaliculi

hair like canals that lacunae to each other and central canal and allows communication

lacunae

small cavities that contain osteocytes

Bone cells

Osteogenic cells, Osteoblasts, Osteocytes, Osteoclasts

Intramembranous Ossification

Bone forms in fibrous membrane, 
Ossification center development, Calcification, Periosteum formation, Red marrow formation

Mesenchymal stem cells form

Capillaries, Osteogenic cells,

Ossification center

Cluster of osteoblasts

Osteoblasts secrete osteoid

Un-calcified matrix, Calcifies over few days

Calcitonin

Secreted by thyroid gland, Released in response to high blood calcium,
Lowers blood calcium concentration,
May inhibit bone loss in pregnant and lactating women, important in children

Calcium Homeostasis

Regulated by three hormones Calcitonin, 
Calcitriol, parathyroid hormone