W10 Skeletal System Flashcards

1
Q

Describe the functions of the skeletons and bone tissues?

A

The skeletal system has a number of important functions:

Support

Protection

Assistance in moving

Mineral homeostasis

Blood cell production

Triglyceride storage

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

Describe support in the skeletal system

A

Provides a structural framework for the soft tissues of the body

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

Describe protection in the skeletal system

A

The skeleton protects internal organs

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

Describe assistance in moving

A

Movement of the skeletal muscle attaches to bones, assist in contraction

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

Describe mineral homeostasis

A

Osseous tissue stores severval minerals (calcium & phosphorous, bones can release minerals to maintain homeostatic levels

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

Describe Blood cell production

A

Blood cells are produced by red bone marrow, which is found in certain bones

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

Describe Triglyceride storage

A

Yellow bone arrow consists mainly of adipocytes that store triglycerides

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

Describe the gross anatomy of a typical long bones

A

Epiphysis (bone end) ↓ Diaphysis (bone shaft) ↓ Epiphysis (bone end)

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

What are the 6 classifications of bones?

A

Long bone

Short bone

Flat bone

Irregular bone

Sesamoid bone

Sutural bones

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

Describe bone tissue

A

A unique form of hard connective tissue. Collagen fibres and mineral salt crystals (Ca & phosphate) = hydroxyapatite. Bones arr composed of two structures compact (cortical) & spongy (cancellous) bone (Spongy bones contain myeloid tissue)

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

Describe the gross anatomy of a typical long bone of the Epiphysis region

A

Articular cartilage - thin layer of cartilage that covers the surface of the epiphysis that articulates with other bones

Metaphysis- Between diaphysis & epiphysis.

Contains the epiphyseal growth plate in growing bones

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

Describe the gross anatomy of a typical long bone in the Diaphysis reigon

A

Endosteum - a thin connective tissue layer that lines the surface of the medullary cavity

Medullary cavity - A hallow clindrical space within the middle of the diaphysis. Contains yellow bone marrow in adults

Periosteum - a connective tissue layer attached to the outside of the bone

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

Describe the structure of a flat bone

A

Structure of a flat bone similar to a long bone but simpler

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

Describe the blood supply in bone

A

Bone is a living tissue so it contains an extensive network of blood vessels. These vessels overlap so if one becomes damaged the bone will not die because it receives blood from another vessel

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

Describe the chemical composition of the bone

A

Osseous tissue is a type of connective tissue, it contains cells that are surrounded and embedded within a extracellular matrix. Composed of 25% water 24% collagen fibers 50% crystallized mineral salts

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

What are the cells of osseous tissue?

A

Osteoprogenitor (osteogenic) Osteoblasts Osteocytes

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

Define Osteoprogenitor cells

A

They are unspecialized stem cells, they are the only bone cells that can divide. Important in fracture repair

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

Define Osteoblasts

A

Synthesis and secrete collagen fibres and other components of the extracellular matrix.

They initiate calcification - bone formation also know as ossification

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

Define Osteocytes

A

Mature bone cells and most numerous cells. Responsible for day to day function of metabolism of osseous tissue.

Exchange aided by cytoplasmic projections in canaliculi (little canals, caneloni) FORMED WHEN OSTEOBLASTS BECOME SURROUNDED WITH BONE MATRIX

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

Define Osteoclasts

A

Large multinucleate cells, release enzymes and acids that digest the extracellular matrix. Involved in resorption of osseous tissue (important for development, maintainance and repair)

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

Describe the histology of a compact &spongy bone

A

Compact bone: diaphysis of long bones, surface of short, flat and irregular bones

Spongy bone - epiphysis of long bone, most of short flat and irregular bone.

22
Q

Describe the histology of a compact bone structure

A

Compact bones contains very few spaces. It provides protection and support and resists stress of weight and movement.

Its ↑ tensile strength is due to the type of materials and how its arranged

23
Q

What are the components of bone structure?

A

Osteon - repeating structural unit of compact bone. Consist of a central canal containing blood vessels surrounded by concentric lamellae, osteocytes, lacuna and canaliculi.

Concentric lamellae (thin layer) - rings of hard, calcified extracellular matrix

Lacuna - small space located between the lamellae, these spaces contain osteocytes

Canaliculi - small channels filled with cellular projections & extracellular fluid that radiate from lacuna, provides routes for oxygen and nutrients to each osteocytes

24
Q

What are the two types of canals in compact bone structure?

A

Central canals - run though the centre of osteons & connect with perforating canals, surrounded by concentric lamellae

Perforating canals - allow blood vessels, lymphatic vessels and nerves to enter compact bone

25
Q

What are the differing lamellae (layers) of compact bone?

A

Interstitial lamellae - areas between osteons, also contain lacuna, canaliculi, & osteocytes. Contain fragments of old osteons that have been broken down during bone remodeling.

Circumferential lamellae - Lamellae that surround the rest of the bone

26
Q

Describe the histology of spongy bone

A

Contains lamellae that are arranged into colums called trabeculae. These spaces make this tissue light

27
Q

Define trabeculae

A

Contain osteocytes within lacuna, canaliculi connect lacuna. Trabeculae orientate towards lines of stress.

28
Q

Describe bone formation

A

There are two methods of bone formatiom during embryonic development:

Intramembranous ossification- flat bones of the skull and mandible

Endochondral ossification: involves the replacement of cartilage with osseous tissue

29
Q

Describe endochondral ossification

A

Mesenchymal (stem) cells of the embryo come together (condense) and differentitate into chondroblasts that produce a hyline cartilage model of the future bone.

Cartilage is mineralised and remodeled to produce bone

30
Q

Describe how epiphyseal plates allow long bones to grow

A

Mesenchymal cells cluster together and condense form a modle of the future bone

→ These develop into chondroblasts that produce hyaline cartilage model of the bone

→ hyaline cartilage is mostly type II collagen and chondroitin → chondroblasts turn into chondrocytes

→ cartilage grows & chondrocytes undergo hypertrophy (larger) and burst which lead to calcification

→primary ossification centre a nutrient artery penetrates into the calcifying cartilage model &; stimulates production of osteoblasts = osseous tissue spreads

→ osteoclasts breakdown some of the newly fored bone @ the medullary cavity

→ development of secondary ossification centre (no medullary cavity forms in this reigon)

→ formation of articular cartilage and epiphyseal plate to cartilage articulation

31
Q

How do long bones grow after birth?

A

Long bones continue to lengthen until adolescene, through additional bone tissue at the epiphyseal plate.

Also increase in wirth through appositional growth. On the epiphyseal side of the epiphseal plate, cartilage is formed.

On the disaphysis side cartilage is ossified and the diaphysis grows in length

32
Q

Describe on a cellular level how bone grows and lengthens

A

Resting zone - nearest the epiphysis. Anchors epiphyseal plate to the epiphysis.

Proliferating zone: chondrocytes are dividing and producing cartilage

Hypertrophic zone - chondrocytes mature and expland

Calcification zone - matrix calcifies chondrocytes die Ossification zone - osteoblasts replace the calcified cartilage with ossesous tissue

33
Q

What are the factors affecting bone growth?

A

Adequate diety intake of minerals and vitamins.

Calcium, phosphorous, fluoride, magnesium, iron,

Vita A, C, B12, D and K,

Weight bearing exercise,

insulin-like growth factor

34
Q

Describe the process of bone remodelling

A

Refers to the ongoing replacement of old osseous tissue by new osseous tissue . Osteoclasts breakdown the extracellular matrix and then osteoblasts replace it with new extracellular matrix

35
Q

What is the function of bone remodelling?

A

Renews old osseous tissue before deterioration sets in. Distrubutes bone extracellular matrix along the lines of mechanical stress

36
Q

Name the two principal divisions of the adult skeleton

A

Axial skeleton - central core of the body including vertebrae, head and trunk

The appendicular skeleton - appendages and support structures including bones of the limbs, hips and shoulders

37
Q

Describe the two major types of markings found on bone surfaces

A

Depressions & openings - allow the passage of soft tissue (blood vessels/nerves)

Processes - projections or outgrowth that help form joints or serve as attachment points for ligaments and tendons

38
Q

Identify the component of the axial skeleton

A

Atlas & axis Cervical (7) Thorasic (12) Lumbar (5) Saccrum (5) Coccyx

39
Q

Identify the components of the appendicular skeleton

A
  • Frontal bone of skull
  • Parietal bone of skull
  • Temporal bone of the skul
  • Occipital bone of the skull
  • Vertebrae collum regions
  • Vertebral cody - vertebral foramen, spinous process and transverse process C1 ( atlas) C2 (axis)
  • Sacrum
  • Sternum
  • Clavicle
  • Scapula
  • Humerus
  • Radius
  • Ulna Carpals, metcarples, phalanges
  • Hip bone
  • Femur
  • Patella
  • Tibia
  • Fibula
  • Tarsals, metatarsals, phalanges of foot
40
Q

What is an articulation ?

A

Points of contact between two bones, bone and teeth , bone and cartilage

41
Q

How do you classify articulations based on movement?

A

Based on the degree of movement, into three categories: Synarthroses - immovable joints Amphiarthroses - slightly moveable Diarthroses - a freely moveable joint

42
Q

Name and describe articulations based on their structure

A

Fibrous joints - bones held together by dense connective tissue Cartilaginous joints - bones are held together by cartilage Synovial joints - there is a synovial cavity and bones are held together by an articular capsule

43
Q

Define fibrous joints and provide examples

A

Sutures - bone of the skull held together by a thin layer of connective tissue.

Syndesmoses - fibrous bands connect two bones (tibia and fibia) (amphiarthroses)

Gomphoses - PDL attaches tooth to socket (synarthroses)

44
Q

Define Cartilaginous joints

A

Synchondroses where the connection between bones is formed by hyaline cartilage (epiphysis to diaphysis = Synarthroses

Symphyses - where a broad flat disc of fibrous cartilage connnects to bones

45
Q

Define Synovial joint

A

Characterised by a synovial cavity between articulating bones, allows cavity to freely move. (Diarthroses) Includes:

Articular cartilage - lines the surface of the articulating surfaces of bone,

Synovial fluid - secreted by the synovial membrane, contains hyaluronic acid. Acts to reduce friction, absorb shocks, supply nutrients & remove wastes

46
Q

What are the 6 types of synovial joints?

A

Pivot joint Gliding joint Condyloid Ball and socket Saddle joint Hinge joint

47
Q

Define pivot joint

A

Only allows rotation around its own axis. (cc1,c2 - atlas axis)

48
Q

Define hinge joint

A

Produce angular open and closing like a door hinge

49
Q

Define saddle joint

A

Allows movement around 3 axis, side to side, up and down, and rotation

50
Q

Define Planar/gliding joints

A

Flat or slightly curved. Side to side, back and forth gliding movement

51
Q

Define Condyloid joint

A

Allows movement around 2 axes, up and down, side to side

52
Q

Define Ball and socket joint

A

Allows movement around all three axes and in all directions