Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Tissues of the Body > Lecture 4.1: Cartilage and Bone > Flashcards

Lecture 4.1: Cartilage and Bone Flashcards

1
Q

What is Cartilage?

A

A form of connective tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Where is Cartilage found?

A

In nearly all joints

In structures that must be deformable and strong

Cartilage forms a template for the development of many bones in utero

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

General characteristics of Cartilage

A

Pliant
Resists compression
Avascular
Not innervated
Comprised of two cell types: chondroblasts and chondrocytes which produce
ECM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Types of Cartilage (3)

A

1) Hyaline Cartilage
2) Elastic Cartilage
3) Fibrocartilage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Hyaline Cartilage

A

ECM contains:
- Proteoglycans
- Hyaluronic acid
- Type II collagen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Elastic Cartilage

A

Similar to hyaline cartilage

But it also contains many elastic fibres

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Fibrocartilage

A

Similar to hyaline cartilage

But matrix contains abundant type I collagen fibres

Comprised of dense regular connective tissue and hyaline cartilage

Contains fibroblasts and chondrocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Location of Hyaline Cartilage

A

Articular cartilage covers the ends of most bones and movable joints

Costal cartilages connect ribs to sternum

Larynx and trachea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Features of Hyaline Cartilage

A

It is is covered by a fibrous perichondrium (except at the articular surfaces of synovial joints)

Large amounts of hyaluronic acid means that hyaline cartilage is well hydrated

It is pliable and resilient under pressure

Large ratio of GAGs to collagen in the ECM facilitates diffusion of substances between chondrocytes and blood vessels surrounding the cartilage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Articular Cartilage has no perichondrium. Where does it get its nutrients from?

A

The surrounding joint fluid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

The Extracellular Matrix (ECM) of Hyaline Cartilage

A

Comprised of type II collagen, water and ground substance (GAGs such as
hyaluronic acid and proteoglycans)

Hyaluronate proteoglycan aggregates are resistant to deformation

Negative charges on surface of GAGs strongly attract polarised H2O molecules forming a hydrated gel.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Appositional Growth

A

The increase in the diameter of bones by the addition of bony tissue at the surface of bones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Interstitial Growth

A

Interstitial growth is a bone growth which results in the lengthening of the bone

This growth occurs within the lacunae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Perichondrium

A

A dense layer of fibrous connective tissue that covers cartilage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Osteoarthritis

A

The most common form of arthritis, prevalence increasing with age

Results from focal and progressive hyaline articular cartilage loss with changes in underlying bone; Soft tissue structures in and around the joint also affected

Severe joint injury has a high likelihood of eventual osteoarthritis, likewise obesity increases the risk.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Growth Plates

A

Hyaline cartilage forms epiphyseal growth plates at the metaphysis of bones

This is where chondrocytes undergo a sequence of cell division and hypertrophy, followed by death and ossification by invading osteoblasts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Locations of Elastic Cartilage

A

External ear (pinna)
External acoustic meatus
Auditory tube
Epiglottis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Locations of Fibrocartilage

A

• Intervertebral discs
• Articular discs of the sternoclavicular and
temporomandibular joints
• Menisci of the knee
• Pubic symphysis
• Entheses (between tendon and bone)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Fibrocartilage in an Intervertebral Disc

A

Annulus fibrosus (tough circular exterior of the intervertebral disc), chondrocyes in lacunae are embedded in large bundles of type I collagen fibres

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Meniscal Damage

A

The menisci of the knee are formed of fibrocartilage discs separating femur and tibia.

Menisci prevent degeneration of articular cartilage underneath

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Meniscal Damage: Most Common Causes

A

Sports-related injuries are most common cause of meniscal lesions in young people

Long-term degeneration from use is most common cause of meniscal lesions from middle-age

22
Q

Features of Bones

A

• Strength and rigidity enables forceful muscle
contractions to result in movement
• Provides protection for internal structures
• Highly vascular and innervated
• Adapts to changing mechanical demands
• Regenerates following injury
• Mineral storage
• Blood cell formation

23
Q

Divisions and Classifications of Bones

A

1) Axial skeleton
2) Appendicular skeleton
3) Shapes of Bones

24
Q

Divisions and Classifications of Bones: Axial Skeleton

A

Skull
Vertebral column
Ribs
Sternum
Hyoid

25
Divisions and Classifications of Bones: Appendicular Skeleton
Everything else except Skull, Vertebral column, Ribs, Sternum, Hyoid
26
Divisions and Classifications of Bones: Shapes of Bones
Long Short Flat Irregular Sesamoid Pneumatic
27
Bone Composition
Inorganic: calcium hydroxyapatite crystals give strength Organic: type I collagen confers flexibility and resistance to stress
28
Types of Mature Bone Structure
Cancellous (spongy) bone is light and provides spaces for bone marrow Compact (cortical) bone forms external surfaces and constitutes 80% of skeletal mass.
29
Organisation of Cortical Bone
Osteon (lamellar structure provides slippage panes, allowing a degree of deformation) Haversian (central) and Volkmann’s (perforating) canals carry blood vessels, lymph vessels and nerves Cortical bone is surrounded the periosteum
30
Structures within an Osteon
Osteocyte in lacuna Canaliculi (Osteocytes have very slender cytoplasmic processes that reach out to adjacent osteocytes) Haversian (or central) canal Lamella of adjacent osteon
31
Cancellous (Spongy) Bone
Osteocytes reside in lacuna between lamellae (which are more irregular) Arranged in trabeculae Space for Adipose (yellow marrow) and haemopoietic cells (red marrow) between trabeculae Type 1 Collagen
32
Internal Trabeculae Structure
Osteocytes Osteoclasts Interstitial Lamellae Osteoblasts aligned along trabeculae of new bone
33
How much bone is turned annually?
5-10% of adult bone turns-over annually
34
Bone Remodelling Unit Components
A cutting cone of osteoclasts A reversal zone containing osteoprogenitors A closing cone where osteoblasts secrete the organic components of bone (osteoid) This process is accompanied by angiogenesis (formation of new blood vessels)
35
What factors affect bone remodelling?
Largely dictated by the mechanical loading applied to bone Bone resorption increases when gravitational forces are reduced Age (rate of remodelling decreases) Increased sport activity (can cause bone hypertrophy)
36
How can bones resist fracture?
Due to balance between flexibility and rigidity Lamellae are able to “slip” relative to each other to help disperse forces Fractures occur when the forces applied are too strong
37
Stages of Fracture Repair (4)
1) Haematoma: Torn vessels bleed, forming a blood clot 2) Soft (fibrocartilage) callus: Clot is removed by macrophages and replaced by a mass of procallus tissue comprised of fibroblasts and collagen 3) Hard (bony) callus: Callus is invaded by blood vessels and osteoblasts. Fibrocartilage is gradually replaced by woven bone. 4) Remodelling: Woven bone remodelled as compact and spongy bone
38
Osteogenesis/ Ossification
It is when new bone is formed
39
Endochondral Ossification
A pre-existing hyaline cartilage template is replaced by bone Osteoblasts from circulating osteoprogenitors invade the cartilage, depositing osteoid (protein matrix) as a substrate for calcification Most of the bones of the body develop in this way
40
What is the Osteoid?
The organic component of bone Largely comprised of type I collagen (secreted by osteoblasts) Undergoes calcification as hydroxyapatite crystals become embedded between collagen fibres
41
Intramembranous Ossification
Bone formation takes place within condensations or “membranes” of mesenchymal tissue Osteoblasts differentiate from local mesenchymal stem cells and deposit osteoid Most flat bones develop in this way
42
Bone formation in a 14 week foetus: what stain?
Alizarin Red
43
Diaphysis
Shaft or central part of a long bone
44
Epiphysis
The expanded end of the long bones in animals
45
Metaphysis
The wide portions of long bones and the regions of the bone where growth occurs
46
Medullary Cavity
The hollow part of bone that contains bone marrow
47
Epiphysis of an adult long bone
Epiphyseal growth plates of long bones are no longer visible after the cessation of growth
48
Endochondral Ossification in Utero (1ary)
1) Skeletal elements are initially composed of hyaline cartilage 2) Late in the 1st trimester, a bone collar develops around the diaphysis long bone, with degeneration of underlying cartilage 3) Invasion of capillaries and osteoprogenitors create a primary ossification centre; Osteoid undergoes calcification to form woven bone
49
Endochondral Ossification in Adolescence (2ndary)
4) Secondary ossification centres appear in the epiphyses around the time of birth 5) In childhood, primary and secondary ossification centres are separated by the epiphyseal growth plate that allows elongation 6) No further elongation can occur when the growth plates close, but an osteoblast reservoir in the periosteum allows thickening
50
Appositional Growth
Occurs when chondroblasts secrete new matrix along existing surfaces and this causes the cartilage to expand and widen
51
Interstitial Growth
Chondrocytes secrete new matrix within the cartilage and this causes it to grow in length

Tissues of the Body (18 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions