The Musculoskeletal System 1. Mineral storage (calcium Ca2+ & phosphate
PO43- )
1. Describe and examine: The function of 2. Blood cell formation (in red marrow of some
bone; Bone tissues (structure); Types of bones)
bone classifications. 3. Fat storage (in yellow marrow)
2. Discuss why bone remodelling occurs and 4. Hormone production
the cells that cause it
3. Examine some common bone ① BONE STRUCTURES
homeostatic imbalances (fractures and Bone Tissue
osteoporosis).
Compact (cortical) bone:
Bones - INTRODUCTION TO BONES Looks solid (no holes visible
2 major subdivisions of the skeleton to the naked eye), is strong
Axial skeleton - skull, vertebral column, and resists internal forces.
ribcage (light yellow below) Spongy (trabecular) bone:
Appendicular skeleton - arms, legs, shoulder Structure looks like
bones, hip bones (blue below) honeycomb, resists strain.
① FUNCTIONS OF BONES 💡 why 2 types of bone tissue? - Mechanical
properties reflect response to loading or
Body consists of lever systems that facilitate deformation
movement (bones and joints), 3 types of levers
(seesaws)(component placing differs) Mechanical Properties
Stress: measure of the internal force acting
Bones – Lever arms on a material (strength).
Joints – Pivot sites Strain: measure of deformation i.e., how well
(Fulcrums) something will change shape without being
damaged (flexibility).
Muscles - Provide the effort
forces to move loads. Stress and strain on area = bone type
Mechanical function: The role of a component in Summary of bone tissue types (MF’s)
the function and assembly of the human body. Compact Bone Spongy Bone
Function = movement in this module. Can w/stand greater w/stand greater strain
stress i.e., it is i.e., more flexible.
The mechanical functions of bone
stronger.
💡 SPA – mechanical pool Can withstand less
Can withstand less stress i.e., not as
1. Support: e.g., bones in lower body support strain i.e., less flexible. strong.
trunk, vertebral column support the torso of
the body. Found in places where Found where shock
2. Protection: e.g., vertebrae protect spinal we want minimal absorption needed.,
column, rib cage protects the vital organs in flexibility and where we want some
the torso, skull bones protect the brain. bending, we find give and flexibility to
3. Anchorage: for skeletal muscles and compact bone. cushion
Solid look Honeycomb.
ligaments e.g., via bone projections like
tubercles, tuberosities, condyles etc.
4. ① Types of Bones
Non-mechanical (biological) functions of
bone
, Long bones Irregular bones 💡Blast – Like gun shooting new bone cells to
bone.
Remodelling is regulated by:
humerus
Maintaining calcium ion (Ca2+) levels in the blood
(Ca2+ reduction -add- stimulates osteoclast
Vertebrae (right lateral activity).
view) Keeping bone strong by applying stress via
Flat bones Short bones
muscle and gravitational forces i.e., exercise!!!
Talus (middle
Sternum of heel foot stress à breakage à remodelling
and lower leg
bones.) ③ HOMEOSTATIC IMBALANCES IN BONE
Fractures
Long Bones Bones can w/stand very large forces – too large à
Long bones: Bones that form our limbs (levers). bone begins to fail i.e., fracture occurs.
Key structural elements of long bones CALCULATION - Examining a stress vs strain
Diaphysis/shaft: long axis of bone. curve for bone.
Constructed of compact bone. Stress vs strain curve: Shows when a fracture
Epiphyses: Ends of long bones. Constructed of will occur.
spongy bone
Epiphyseal plate (or growth plate): Site of
longitudinal bone growth.
Epiphyseal line: Former site of epiphyseal
plate. (Used to be).
TMI: Short, irregular and flat bones typically
consist of spongy bone sandwiched by compact
bone
② BONE
REMODELLING
Bone remodelling
(includes replacement,
change, growth etc.
replaces 5-10% of
skeleton yearly. Occurs
through bone resorption and bone deposition
Bone resorption: is carried out by osteoclast
activity.
(osteoclast = cell that breaks down bone).
💡Clast – Clears dead bone cells
Bone deposition: is carried out by osteoblast
activity
(osteoblast = cell that forms bone).
PO43- )
1. Describe and examine: The function of 2. Blood cell formation (in red marrow of some
bone; Bone tissues (structure); Types of bones)
bone classifications. 3. Fat storage (in yellow marrow)
2. Discuss why bone remodelling occurs and 4. Hormone production
the cells that cause it
3. Examine some common bone ① BONE STRUCTURES
homeostatic imbalances (fractures and Bone Tissue
osteoporosis).
Compact (cortical) bone:
Bones - INTRODUCTION TO BONES Looks solid (no holes visible
2 major subdivisions of the skeleton to the naked eye), is strong
Axial skeleton - skull, vertebral column, and resists internal forces.
ribcage (light yellow below) Spongy (trabecular) bone:
Appendicular skeleton - arms, legs, shoulder Structure looks like
bones, hip bones (blue below) honeycomb, resists strain.
① FUNCTIONS OF BONES 💡 why 2 types of bone tissue? - Mechanical
properties reflect response to loading or
Body consists of lever systems that facilitate deformation
movement (bones and joints), 3 types of levers
(seesaws)(component placing differs) Mechanical Properties
Stress: measure of the internal force acting
Bones – Lever arms on a material (strength).
Joints – Pivot sites Strain: measure of deformation i.e., how well
(Fulcrums) something will change shape without being
damaged (flexibility).
Muscles - Provide the effort
forces to move loads. Stress and strain on area = bone type
Mechanical function: The role of a component in Summary of bone tissue types (MF’s)
the function and assembly of the human body. Compact Bone Spongy Bone
Function = movement in this module. Can w/stand greater w/stand greater strain
stress i.e., it is i.e., more flexible.
The mechanical functions of bone
stronger.
💡 SPA – mechanical pool Can withstand less
Can withstand less stress i.e., not as
1. Support: e.g., bones in lower body support strain i.e., less flexible. strong.
trunk, vertebral column support the torso of
the body. Found in places where Found where shock
2. Protection: e.g., vertebrae protect spinal we want minimal absorption needed.,
column, rib cage protects the vital organs in flexibility and where we want some
the torso, skull bones protect the brain. bending, we find give and flexibility to
3. Anchorage: for skeletal muscles and compact bone. cushion
Solid look Honeycomb.
ligaments e.g., via bone projections like
tubercles, tuberosities, condyles etc.
4. ① Types of Bones
Non-mechanical (biological) functions of
bone
, Long bones Irregular bones 💡Blast – Like gun shooting new bone cells to
bone.
Remodelling is regulated by:
humerus
Maintaining calcium ion (Ca2+) levels in the blood
(Ca2+ reduction -add- stimulates osteoclast
Vertebrae (right lateral activity).
view) Keeping bone strong by applying stress via
Flat bones Short bones
muscle and gravitational forces i.e., exercise!!!
Talus (middle
Sternum of heel foot stress à breakage à remodelling
and lower leg
bones.) ③ HOMEOSTATIC IMBALANCES IN BONE
Fractures
Long Bones Bones can w/stand very large forces – too large à
Long bones: Bones that form our limbs (levers). bone begins to fail i.e., fracture occurs.
Key structural elements of long bones CALCULATION - Examining a stress vs strain
Diaphysis/shaft: long axis of bone. curve for bone.
Constructed of compact bone. Stress vs strain curve: Shows when a fracture
Epiphyses: Ends of long bones. Constructed of will occur.
spongy bone
Epiphyseal plate (or growth plate): Site of
longitudinal bone growth.
Epiphyseal line: Former site of epiphyseal
plate. (Used to be).
TMI: Short, irregular and flat bones typically
consist of spongy bone sandwiched by compact
bone
② BONE
REMODELLING
Bone remodelling
(includes replacement,
change, growth etc.
replaces 5-10% of
skeleton yearly. Occurs
through bone resorption and bone deposition
Bone resorption: is carried out by osteoclast
activity.
(osteoclast = cell that breaks down bone).
💡Clast – Clears dead bone cells
Bone deposition: is carried out by osteoblast
activity
(osteoblast = cell that forms bone).
