Skeletal System Flashcards
Describe the Anatomical position
Person stands erect with feet parallel flat on the floor, palms facing forward and arms at the sides of the body
What does supine describe
the body laying down face up
What does prone describe
body laying down face down
What is the definition of the following:
Medial
Lateral
Bilateral
Unilateral
Ipsilateral
Contralateral
Proximal
Distal
Anterior
Posterior
Superior
Inferior
Nearer the midline
Away from the midline
Both sides
One side
Same side
Opposite side
Nearer the trunk
Further from the trunk
Nearer the front
Nearer the back
Towards the top
Towards the bottom
What plane separates the body from front to back
Coronal/Front plane
What plane separates body from left and right
Sagittal plane
What plane separates the body from bottom to top
Horizontal/Transverse plane
How many bones are there in the human skeletal system
206
What percentage of the body weight is the skeletal system
18%
List 8 functions of the skeletal system.
Provides protection for internal organs.
Supports framework for the body.
Forms boundaries e.g skull
Attachment for tendons and ligaments
Permits movement of joints
Haematopoiesis - formation and development of blood cells from the red bone marrow.
Mineral homeostasis - calcium and phosphate
Tryglycedride storage - (yellow bone marrow
What are Osteogenic cells and what ais their function
Osteogenic cells are bone stem cells that are unspecialised, their function is to go on and become Osteoblasts
What are Osteoblasts and what is their function
Osteoblasts are immature cells that are bone building cells.
They synthesis and secrete collagen and other components of bony matrix such as Chondroitin.
They get trapped in their own matrix and then go on to become Osteocytes
What are Osteocytes and what is their function
Osteocytes are fully matured cells
They maintain daily metabolism in bone and the exchange of nutrients.
What are Osteoclasts and what is their function
Osteoclasts are huge cells made up of over 50 monocytes (white blood cells)
On the side facing the bone they have a ruffled board that secretes powerful lysosomal enzymes and acids, which digest bone matrix
What does resorption refer to in bone cells
The breakdown of bone matrix
What does resorption refer to in bone cells
The breakdown of bone matrix
Fill in the xxxx
xxxxxx and xxxxxx work together to xxxxx bone throughout life. Excess xxxxx activity leads to a loss of xxxx xxxx and can lead to xxxxxxx
Osteoblasts
Osteoclasts
Remodel
Osteoclast
bone density
Osteoporosis
What are the 2 types of bone called
Compact and Spongy bone
How much of the skeleton is made up of compact bone
80%
Where is compact bone found
Beneath the Periosteum of all bones
What cells does bone contain
Osteogenic, Osteoblasts Osteocytes and Osteoclasts
Which bone contains few spaces and is strong? What kind of tissue is bone made up of?
Compact Bone and Connective tissue
Where do we mainly find compact bone
Found beneath the Periosteum of all bones and makes up the bulk of the diaphysis in long bone
What is and Osteon and how is it aligned
Structural Unit of Compact bone and it is aligned in the same lines as stress
What are the 4 parts that Osteons are made up of and describe each.
Haversian Canal - contains the blood vessels and the nerves
Lamellae - Concentric rings of calcified extracellular matrix containing minerals and collagen
Canaliculi - a mini system of interconnected canals that provide a route for minerals and waste
Lacunae - small spaces filled with Osteocytes
Describe Spongy Bone
Spongy bone does not contain Osteons. It is an irregular lattice of thin columns called Trabeculae arranged along the lines of stress.
Macroscopic spaces between Trabeculae helps to keep bone lighter and can be filled with bone marrow. They contain blood vessels that nourish the bone.
Define a long bone
Bones that have a greater length than width
Describe a long bone
Long bones contain a Diaphysis and 2 heads Epiphyses.
They are slightly curve for strength which allows for better force distribution.
They contain mainly compact bone in the diaphysis and spongy bone in the Epiphyses.
Examples include the femur, tibia and humerus
Where do we find the Epipysises
forms the proximal and distal ends of long bones
What separates the Epiphysis and Diaphysis what is made up of. What does is do?
The Epiphyses and Diaphysis are separated by the epiphyseal plate which is a layer of hyaline cartilage that allow the diaphysis to grow in length.
What is the structure of epiphysis
Epiphysis contains a thin outer region of compact bone covered by articular/Hyaline cartilage and inner bone with red bone marrow
What does Diaphysis describe
Tubular shaft of long bones
What is the outside of compact bone covered by
Periosteum
Where do we find the central medullary cavity and what does it contain?
It is found in the Periosteum and contains red/yellow bone marrow
Does all bone marrow start of as Red or Yellow
All bone marrow starts at birth as red and gradually some of the red bone marrow is replaced with yellow bone marrow (fat) which
Why would the body need to convert yellow bone marrow.
The body can covert yellow bone marrow very quickly to red bone marrow if needed. For example if some one has had an accident or Hemorrhaging and will provide more blood cells.
What does peri mean?
Surrounding e.g periosteum surrounding bone
Where do we find the Periosteum?
Surrounding the external surface of the bone that is not covered in cartilage.
What replaces the Periosteum on joint surfaces
Hyaline cartilage
Fill in the gaps
The Periosteum is a xxxx-xxxxx, highly-xxxxx xxxxx that xxxxx bone and serves as an xxxxxx for xxxxx and xxxxx
pain-sensitive
vascular membrane
protects
attachment for ligaments and tendons
How do bones receive oxygenated blood?
Periosteal arteries enter the diaphysis through many perforating canals
Describe the structure of the Periosteum
It is double layered membrane containing a tough fibrous outer layer that protects bone.
Inner ‘Osteogenic layer’ that contains Osteoblasts and Osteoclasts, assisting in bone growth and repair.
What type of bone is the Patella
Sesamoid bone
Where do we find irregular shaped bones
Vertebrae
Give examples of 2 flat bones
Scapular and skull or pelvis
What is the Diaphysis
The central shaft between proximal and distal Epiphyses
Define what is means to ossify something
To harden something
What does Ossification mean?
To produce a bone
When do our bones stop remodeling
They don’t we continue to remodel our bones throughout life.
What are the 2 Ossification pathways used to produce bone and what do they do? Give 2 examples of each?
- Intramembranous ossification -
Bone develops from connective tissue sheets
Flat bones (i.e the skull) and the clavicles develop this way. - Endrochondral ossification - Bone develops by replacing hyaline cartilage i.e ribs, arms and leg bones
What does endo stand for
Within
What does chondral stand for
Cartilage
What is the name of the plate needed for bones to grow
Epiphyseal Growth plate
What are the 2 ends of the Epiphyseal plate called and define
Proximal Epiphyseal Growth Plate - Growth plate nearer the trunk
Distal Epiphyseal Growth Plate - Growth plate further from the trunk
Where do we find the Epiphyseal Growth plate
Found in long bones between the Epiphysis and the Diaphysis
Where do we find Hyaline Cartilage
In the Epiphyses top and bottom of bones
What is produced in the epiphyses and what does it do
Osteoblasts are produced, ossifying the bone matrix
At what age does the Epiphyseal Growth Plate ossify?
Between 18 - 21 years of age
What remains after the Epiphyseal Growth plate has ossified
Epiphyseal line remains
What might we see if a bone fracture damages the epiphyseal plate during childhood?
The bone may grow shorter - seeing a discrepancy in leg length
How can bones grow in thickness
Using Osteoblasts in the Periosteum
Describe the activity within the growth plate
Cartilage cells (Chondrocytes) undergo mitosis
Then chondrocytes stop dividing
Then minerals start to deposit, capillaries invade and deliver Osteoblasts/Osteoclasts and new bone is formed.
What are Chondrocytes
Cartilage cells