Cartilage and Skeleton Flashcards by Zahara Hill

Components of the Skeleton

Components
• Bones
- Adult has ~206
- Hard, calcified matrix
- Calcium reservoir
• Cartilage
-Provides flexibility
• Nerves
• Blood vessels
• Epithelial tissue

How well did you know this?

Not at all

Perfectly

What are Chondroblasts?

Chondroblasts
-Secrete collagen & elastic fibers for support

How well did you know this?

Not at all

Perfectly

Are there blood vessels or nerves within cartilage?

No blood vessels or nerves within cartilage

How well did you know this?

Not at all

Perfectly

What are the types of cartilage?

• There are 3 types of cartilage:
1. Hyaline
2. Elastic
3. Fibrocartilage

How well did you know this?

Not at all

Perfectly

Components of Hyaline Cartilage

• Most abundant
• Mostly collagen fibers
• Firm matrix cushions and resists compression

How well did you know this?

Not at all

Perfectly

Where is Hyaline Cartilage found?

• Cartilages in the nose
• Articular cartilage of a joint
- ( the smooth, white tissue that covers the ends of bones where they come together to form joints)
• Costal Cartilage
- (serve to prolong the ribs forward and contribute to the elasticity of the walls of the thorax)
• Thyroid Cartilage
• Cricoid Cartilage
- (the ring-shaped cartilage of the larynx.)
• Trachea

How well did you know this?

Not at all

Perfectly

Components of Elastic Cartilage

Elastic Cartilage
• Mostly elastic fibers, some collagen
• Able to withstand repeated bending

How well did you know this?

Not at all

Perfectly

Locations of Elastic Cartilage

Locations:
• Epiglottis
• Pinna (outer ear)

How well did you know this?

Not at all

Perfectly

Components of Fibrocartilage

• Higher concentration of collagen fibers than hyaline; no elastic fibers
• Strong! Resists tension and absorbs compressive forces

How well did you know this?

Not at all

Perfectly

Locations of Fibrocartilage

Locations:
• Intervertebral discs
- (lies between adjacent vertebrae in the vertebral column.)
• Menisci
- (protect and cushion the joint surface and bone ends)
• Pubic symphysis
- (joint sandwiched between your left pelvic bone and your right pelvic bone.)

How well did you know this?

Not at all

Perfectly

What is Cauliflower Ear?

• A blow to the ear can result in the perichondrium separating from the deeper elastic cartilage resulting in a hematoma and swelling

How well did you know this?

Not at all

Perfectly

Functions associated with skeleton

• Support
- Framework and support for soft tissues
• Movement
-Works with muscular system to move body
• Protection
- Of the brain, spinal cord, organs of thorax
• Mineral reservoir
- Calcium and phosphates stored in matrix
• Hemopoiesis
-Houses red bone marrow, which produces new blood cells
• Energy storage
-Fat is stored in yellow bone marrow
• Endocrine
-Osteoblasts secrete hormone (osteocalcin) that helps regulate blood sugar levels

How well did you know this?

Not at all

Perfectly

Types of Bone (not shape)

• Spongy bone
-Loosely organized rods of bone called trabeculae
-Found in epiphyses of long bones, interior of flat, short, or irregular bones
• Compact bone
-Lines outer surface of bones

How well did you know this?

Not at all

Perfectly

What is Spongy Bone Better for?

Spongy bone is better for:
• Resisting forces from multiple directions
• Forming a lighter skeleton

How well did you know this?

Not at all

Perfectly

What is Compact Bone better for?

Compact bone is better for:
• Resisting forces from one direction
• Storage of minerals in the matrix

How well did you know this?

Not at all

Perfectly

Structure of Spongy Bone

Made of rods of bone called trabeculae
• Are formed in response to stress placed on the bone
• Trabeculae are lined with endosteum
• Trabeculae contain osteocytes
• Spaces contain red bone marrow

How well did you know this?

Not at all

Perfectly

Structure of Compact Bone

Made of repeating structural units called osteons
• Are long, cylindrical structures
• Run parallel to long axis of bone

How well did you know this?

Not at all

Perfectly

What is the osteon, in compact bone?

The osteon
• Made of concentric circles called lamellae
• Lacunae are between adjacent lamellae
- Osteocytes live in lacunae
• Lacunae are connected by little canals called canaliculi
- Canaliculi allow movement of nutrients and communication between osteocytes

How well did you know this?

Not at all

Perfectly

What is the Haversian/central Canal? (compact bone)

Study These Flashcards

• In the center of the lamellae is a central canal (= Haversian canal)
- Contains blood vessels and nerves
- Perforating canals are how blood vessels reach the central canals

Can Red Blood Cells pass through canaliculi ? (compact bone)

Study These Flashcards

• Red blood cells are too large to pass through canaliculi
• Nutrients must diffuse to osteocytes through canaliculi
- This limits the size of the osteon

Other types of lamellae (compact bone)

Study These Flashcards

• Interstitial lamellae
- Remnants of old osteons
• Circumferential lamellae
- Rings around the circumference of the diaphysis

What direction do adjacent lamellae run?

Study These Flashcards

• Collagen fibers in adjacent lamellae run perpendicular to one another
- This increases strength

Types of bone shapes?

Study These Flashcards

• Long bone
• Short bone
• Flat bone
• Irregular bone

Examples of each type of bone

Study These Flashcards

• Long bone
- Ulna / radius (forearm)
- the femur (thigh bone)
- humerus (upper arm)
• Short bone
- Talus (ankle)
- Capitate (carpal) bone (wrist)
• Flat bone
- Scapula (shoulder blade)
- Sternum (chest)
• Irregular bone
- Sphenoid bone (base of cranium)
- Vertebra (backbone)

Structure of Long Bone

• Epiphyses • Diaphysis • Connective tissue membranes

What is Epiphyses?

Epiphyses • Spongy bone surrounded by compact bone • Red bone marrow is found between trabeculae • Epiphyseal line/plate separates epiphysis from diaphysis • Articular cartilage covers articulating surface

What is the Diaphysis?

Diaphysis • Medullary cavity • Adults: is filled with yellow marrow (adipocytes) • Children: is filled with red bone marrow (hemopoiesis) • Switches to yellow bone marrow between ages 8-18

What is the Connective tissue membranes?

Connective tissue membranes • Periosteum surrounds outer compact bone (except where articular cartilage is present) - Made of dense irregular CT - Perforating fibers attach periosteum to bone (Very strong) - Is osteogenic where touches compact bone --> osteoclasts and osteoblasts are deep to the periosteum and actively remodel the bone

What is the Endosteum?

Endosteum lines inner surfaces (including trabeculae) • Thinner dense CT • Osteogenic (bone forming) • Osteoblasts and osteoclasts are located under endosteum

What is the Arterial Supply to Long Bones?

Nutrient arteries • Pierce periosteum to supply bone with blood • Perforating arteries (inside perforating canals) connect with arteries in central canal - Nutrients travel to osteoclasts via canaliculi

What is the Epiphyseal plate?

Epiphyseal plate = growth plate; site of active growth in long bone

What is the Epiphyseal line?

Epiphyseal line = growth plate becomes ossified; growth in length is complete

Layers for Bone formation

Epiphysis - Resting (quiescent) zone - Proliferation (growth zone) - Hypertrophic zone - Calcification zone - Ossification Diaphysis

What happens in Proliferation zone?

Cartilage cells undergo mitosis

What happens in Hypertrophic zone?

Older cartilage cells enlarge

What happens in calcification zone?

Matrix becomes calcified: cartilage cells die; matrix deteriorating

What happens in Ossification zone?

New bone formation is occuring

What is Intramembranous Ossification

Intramembranous ossification • Connective tissue membranes are replaced by bone • Most of skull and clavicle form this way • Fontanels are remnants of CT membrane

How do osteoblasts become osteocytes?

Osteoblasts produce the matrix; once trapped by matrix are called osteocytes

Steps of Intramembranous Ossification

1. Ossification centers develop in fibrous CT 2. Organic component (osteoid, contains collagen) is secreted then is calcified 3. Immature bone (=woven bone made of trabeculae) is formed 4. Woven bone is remodeled into compact bone (externally) and spongy bone (internally)

What is Endochondral ossification?

Endochondral ossification • Hyaline cartilage serves as a template • Most bones of skeleton form this way -Lower part of skull down (except clavicles) • Epiphyseal plate is a remnant of hyaline skeleton

What is Remodeling?

Remodeling • Occurs under periosteum andendosteum • Continues throughout a lifetime; based on need of blood calcium levels • Osteoclasts secrete HCl which dissolves and releases minerals from matrix • Osteoblasts lay down organic osteoid which fills with minerals

Steps of Bone Fracture Healing

1. A hematoma forms 2. Fibrocartilaginous callus forms 3. Bony callus forms 4. Bone remodeling occurs

What is Osteoporosis?

Osteoporotic: pits on surface of bone indicate where osteoclasts have broken down the matrix • Osteoclasts outpace osteoblasts

What is Osteomalacia?

Osteomalacia • Called rickets in children • Characterized in children as bowed long bones • Bone matrix not properly mineralized • Often a result of a nutritional or UV deficiency resulting in not enough calcium added to matrix • Reason why vitamin D is added to milk

Cartilage and Skeleton Flashcards

(45 cards)