Bone Tissue Lecture 1 Flashcards by a w

6 Main Functions of Bone

Support
Protection
Assisstance in movement
Mineral Homeostasis
Blood cell production
Storage of triglycerides

How well did you know this?

Not at all

Perfectly

Bone Structure: Diaphysis

Description, Example

Description:
* Main bone shaft, long, tubular,
* Predominantly made of compact bone
* Houses yellow bone marrow.

How well did you know this?

Not at all

Perfectly

Bone Structure: Epiphysis

Description, Example

Description:
* Epiphysis: Ends of bones
* Filled with cancellous/spongy bone
* Houses red marrow
* Projections/fossae for articulations.

How well did you know this?

Not at all

Perfectly

Bone Structure: Metaphysis

Description, Example

Description:
* Portion between diaphysis and epiphysis
* Weakest portion of bone,
* Contains epiphyseal plate which becomes epiphyseal line.

How well did you know this?

Not at all

Perfectly

Bone Structure: Medullary (marrow) Cavity

Description, Example

Description:
* Hollow cavity in the diaphysis
* Contains yellow bone marrow and numerous blood vessels
* Lined with endosteum.

How well did you know this?

Not at all

Perfectly

Bone Structure: Endosteum

Description, Example

Description:
* Layer of dense irregular connective tissue that lines the medullary cavity and internal spaces of spongy bone.

How well did you know this?

Not at all

Perfectly

Bone Structure: Periosteum

Description, Example

Description:

“Skin” surrounding bones,
Made of fibrous and cellular layers.

How well did you know this?

Not at all

Perfectly

Bone Structure: Articular (hyaline) cartilage

Description, Example

Description:

Cartilaginous tissue at the ends of bones (covers epiphysis),
Reduces friction and allows movement at articulations.

How well did you know this?

Not at all

Perfectly

Bone Histology: Extracellular Matrix of Bone

Description, Example

Description:
* Organic component of ECM, including collagen fibers and crystallized mineral salts.

How well did you know this?

Not at all

Perfectly

Bone Histology: Ground Substance

Description, Example

Description:
* Inorganic component of ECM, mainly calcium phosphate,
* Provides strength to bone.

How well did you know this?

Not at all

Perfectly

Bone Histology: Hydroxyapatite

Description, Example

Description:
* Formed by the interaction of calcium phosphate and calcium hydroxide,
* Providing the structural rigidity of bone.

How well did you know this?

Not at all

Perfectly

Bone Histology: Osteoprogenitor (osteogenic) Cells

Description, Example

Description:

Unsophisticated stem cells derived from mesenchyme tissue
Capable of mitosis
Develop into osteoblasts.

How well did you know this?

Not at all

Perfectly

Osteoblasts

Description, Example

Description:
* Bone-building cells,
* Secrete collagen and bone matrix proteins to form osteoid
* Initiate calcification.

How well did you know this?

Not at all

Perfectly

Bone Histology: Osteocytes

Description, Example

Description:

Mature bone cells that maintain and monitor metabolic activities
Connected by canaliculi and occupy lacunae.

How well did you know this?

Not at all

Perfectly

Bone Histology: Osteoclasts

Description, Examples

Description:

Bone cells that break down bone tissue in a process called resorption.
Taking calcium from the bone into the bloodstream.
Found on the bone surface, and active osteoclasts are located in Howship’s lacunae.

How well did you know this?

Not at all

Perfectly

Types of Bone Tissue: Compact Bone

Description, Example

Description:

Hard and dense bone tissue, with little or no spaces between cells
Strongest form of bone

Types of Bone Tissue: Compact Bone
Osteons

Description, Example

Description:

Individual structural units of compact bone,
Consisting of concentric lamellae surrounding a Haversian canal.

Types of Bone Tissue: Compact Bone
Interstitial Lamellae

Description, Example

Description:
Lamellae located between osteons, filling spaces not occupied by osteons.

Types of Bone Tissue: Compact Bone
Circumferential Lamellae

Description, Example

Description: Lamellae surrounding the medullary cavity or lying underneath the periosteum.

Types of Bone Tissue: Compact Bone
Haversian (Central) Canals

Description, Example

Description:

Parallel canals running longitudinally along the bone shaft
Conducting blood vessels, lymph vessels, and nerves.
.

Types of Bone Tissue: Compact Bone
Volkmann’s Canals

Description, Example

Description:

Perpendicular canals running superficial to deep
Conducting blood vessels, lymphatic vessels, and nerves through the periosteum.

Types of Bone Tissue: Compact Bone
Lacunae

Description, Example

Description: Small spaces within lamellae containing osteocytes.

Types of Bone Tissue: Compact Bone
Canaliculi

Description, Example

Description:

Small channels radiating in all directions from each lacuna
Filled with fluid and osteocyte filopodia.

Types of Bone Tissue: Spongy Bone

Description, Example

Description:

Also known as trabecular or cancellous bone,
Lacks osteons
Appears spongy due to a lattice and irregular pattern of bone tissue distribution.

Types of Bone Tissue: Spongy Bone Blood Supply ## Footnote Description, Example

**Description:** * Spongy bone has a greater blood supply than compact bone, * Producing red blood cells, white blood cells, and platelets.

Types of Bone Tissue: Spongy Bone Distribution in Bones ## Footnote Description, Example

**Description:** * In long bones, spongy bone is concentrated in the epiphysis, * In flat bones, it predominates the inner structure.

Types of Bone Tissue: Spongy Bone Trabeculae ## Footnote Description, Example

**Description:** The lamellae of spongy bone are arranged into small struts or beams, resembling a "coral reef" appearance.

Bone Formation: Ossification/Osteogenesis ## Footnote Description, Example

**Description:** The process of bone formation begins during the 6th week of embryonic development.

Bone Formation: Endochondral Ossification ## Footnote Description, Example

**Description:** processwhere initial skeleton of the embryo is made of hyaline cartilage, which is replaced by bone. **Hyaline cartilage into bone**

Bone Formation: Intramembranous Ossification

**Description:** * Involves the replacement of sheet-like connective tissue membranes with bony tissue. * Stem cells become osteoblasts in connective tissue, forming dermal/membrane bones.

Primary/Secondary Ossicication Centers

**Primary Ossification Centers:** Appear during prenatal development in the central part of each developing bone. **Secondary Ossification Centers:** Develop in the epiphyseal region after birth.

Intramembranous Ossification:

Dermal/Membrane Bone Formation: Stem cells become osteoblasts in connective tissue, forming dermal/membrane bones.

Growth in length (interstitial growth) Epiphyseal plate

* Hyaline cartilage in metaphysis becomes site for new bone. * After maturity, it turns into epiphyseal line.

# Interstitial growth Resting Cartilage Zone

* Nearest to epiphysis * Small chondrocytes anchor plate to epiphysis

# Interstitial Growth Proliferating Cartilage Zone

* Large chondroblasts replicate and divide * Appears like stacks of coins

# Interstitial Growth Hypertrophic Cartilage Zone

Large, mature chondrocytes in columns

# Interstitial Growth Calcified Cartilage Zone

* Mostly dead chondrocytes; area calcified * Osteoblasts invade to lay down new matrix; diaphysis conversion * Growth in length (interstitial growth)

Growth in thickness (appositional growth)

* Osteogenic cells differentiate into osteoblasts under the periosteum to add bone matrix * Osteoclasts remove matrix at inner surface to enlarge medullary cavity