Download Skeletal system File

Lesson objectives
• List and label the bones that make up the skull
• List and label the bones that make up the axial
skeleton
• List and label the bones that make up the
appendicular skeleton
• Describe the structure and functions of the
skeleton
The Skull
•
•
•
•
•
There are 22 bones in the skull
8 cranial
14 facial
These bones protect the brain
They also provide a surface for muscle
attachment
Cranial Bones
•
•
•
•
•
•
1 x Ethmoid Bone
1 x Frontal Bone
1 x Occipital Bone
2 x Parietal Bones
1 x Sphenoid Bone
2 x Temporal Bones
Facial Bones
• 2x Turbinate Bones
• 2x Lacrimal Bones
• 1x Mandible
• 2x Maxillae (Singular = Maxilla)
• 2x Nasal Bones
• 2x Palatine Bones
• 1x Vomer
• 2x Zygomatic Bones
Side View of Skull
Front View of Skull
Frontal Bone
Nasal Bone
Ethmoid Bone
Lacrimal Bone
Turbinate Bone
Vomer Bone
Palatine Bones
• The palatine bone forms part of the nasal
cavity and hard palate
Palatine Bones
Palatine Bone
Sphenoid Bone
• A bone which forms the base of the cranium,
behind the eye and below the front part of the
brain
• It has two pairs of broad lateral ‘wings’ and a
number of other projections, and contains
two air-filled sinuses
Sphenoid Bone
Ethmoid Bone
• This is an unpaired bone in the skull that
separates the nasal cavity from the brain
• It is located at the roof of the nose, between
the two orbits
Ethmoid Bone
Lacrimal Bones
• Two small bones which form part of the eye
sockets
Lacrimal Bones
Vomer Bone
• The vomer is one of the unpaired facial bones
of the skull
• It is located in the midsagittal line, and joins
with the sphenoid, the ethmoid, the left and
right palatine bones, and the left and right
maxillary bones
Vomer Bone
Structure of Skeletal System
• Human skeleton is made up of 206 bones
• Babies born with over 300 bones
• Bones fuse together over time
• Bone is pound for pound stronger than steel
Structure of Skeletal System
• Human skeleton is made up of 206 bones
• Babies born with over 300 bones
• Bones fuse together over time
• Bone is pound for pound stronger than steel
Axial Skeleton
•
•
•
•
•
Forms the core of the body
Skull
Spine
Sternum
Ribs
The Spine/Vertebral Column
•
•
•
•
•
•
•
•
•
•
Provides support
Protects spinal cord
Comprises 33 bones
7 cervical - top
12 Thoracic - middle
5 Lumbar - bottom
5 Sacrum
4 Coccyx
Sacrum and coccyx are fused, no movement
24 moveable bones
The Spine/Vertebral Column
Thoracic Cage
• Consists of the ribs, sternum and thoracic
vertebrae
• Protects heart and lungs
• 12 pairs of ribs
• 7 true pairs attached to sternum
• 3 false ribs attached to cartilage of the 7th rib
• 2 pairs not attached (floating ribs)
Thoracic Cage
Appendicular Skeleton
•
•
•
•
Shoulder girdle
Upper Limbs
Lower Limbs
Pelvic girdle
Shoulder Girdle
A = Scaphoid B = Lunate
E = Trapezium F = Trapezoid
C = Triquetral
G = Capitate
D = Pisiform
H = Hamate
Bones of Wrist
•
•
•
•
•
•
•
•
•
8 bones
S = Sally - Scaphoid
L = Left - Lunate
T = The - Triquetral/Triquetrum
P = Party - Pisiform
T = To - Trapezium
T = Take - Trapezoid
C = Cathy - Capitate
H = Home - Hamate
Pelvic Girdle
• Two hip bones joined together
• The each hip bone consists of three different
bones:
• Ilium
• Ischium
• Pubis
Pelvic Girdle
Pelvic Girdle
Functions of Skeletal System
•
1.
2.
3.
4.
5.
6.
7.
The skeletal system has 7 major functions:
Movement
Support
Shape
Protection
Muscle attachments
Formation of blood cells
Mineral storage
Muscle Attachment and
Movement
• Muscles attach to bone by tendons
• Muscles contract
• Bones act as levers and help movement
Support and Shape
• Holds weight of the body
• Wouldn’t be able to stand up
• Bones gives shape to structures – skull, ribs
etc.
Protection
•
•
•
•
Helps protect body vital organs and structures
Ribs – heart and lungs
Cranium – brain
Vertebrae – spinal cord
Formation of Blood Cells &
Mineral Storage
• Important minerals (calcium) stored in bone
marrow
• Blood cells created in bone marrow
Structure of Bone
•
•
•
•
•
•
Bone is made from special cells
Osteoblasts
Different types of bone tissue:
Compact
Cancellous or Spongy bone
Marrow
Compact Bone
• Gives bones hardness
• Protects spongy bone
• Provides framework for the bone and body
Cancellous/Spongy Bone
•
•
•
•
Lighter in weight than compact bone
Sponge-like appearance
Web like structure, consists of red bone marrow
Contains blood vessels which carry oxygen and
nutrients
Bone Marrow
•
•
•
•
•
Found inside bone
Main function is the production of blood cells
Two different types:
Red bone marrow
Yellow bone marrow
Red Bone Marrow
• Responsible for producing blood cells
• Babies bones made up of mostly red marrow
• Within a few years red marrow will change to
yellow marrow
• Mainly found in flat, irregular and sesamoid
bones
Yellow Bone Marrow
• Consists mainly of fat cells
• Can be used as energy in extreme starvation
conditions
• Can be converted into red marrow within 2
hours
Bone Types
•
•
•
•
•
Long
Short
Flat
Irregular
Sesamoid
Long Bones
• Characterised by a shaft
• Longer than they are wide
• Made of mostly compact
bone with little spongy bone
• Usually found in the limbs,
fingers and toes
Short Bones
• Usually more cube shaped
• Thin layer of compact bone
covering more spongy bone
• Usually found in the wrist
and ankle
Flat Bones
• Thin, usually curved bones
• Two thin parallel layers of
compact bone sandwiching
a layer of spongy bone
• Found in the skull, scapula
and sternum
Irregular Bones
• Thin layer of compact bone
surrounding spongy bone
• Irregular shape
• Can be found in the vertebrae
Sesamoid Bones
• Bones embedded in tendons
• Increase the distance between
a tendon and a joint
• Increase the leverage of the
muscle
• Example - Patella