Skeletal System Flashcards
What is the Skeletal System defined as?
Defined as the framework of :
* bones
* cartilage
* ligaments
* connective tissues
How many bones is the body composed of?
The body is composed of 206 bones.
Why are bones necessary?
They give the body form and allow joints to produce body motion.
Why must bones be rigid and unyielding?
- To fulfill function
- To be able to adapt & grow as body grows.
(bone growth usually complete by late teens)
Bones are living tissues and contain?
- Rich blood supply that provides oxygen & nutrients.
- An extensive nerve supply.
What are the 5 functions of the Skeletal System?
1) Support
2) Protection
3) Movement
4) Storage
5) Hemopoiesis
What is Skeletal Support?
Provides structural support for entire body.
What is Skeletal Protection?
Delicate tissues are surrounded by skeletal elements.
(ex : The skull protects the brain.)
What is Skeletal Movement?
Bones work with muscles to produce movement.
(“Bones convert muscle into movement”)
What are bones points of attachment to?
Muscles and Tendons
What is Skeletal Storage?
Bones store minerals that distribute to rest of body.
* Calcium
* Phosphorus
(main minerals)
What are lipids used for when stored in bones?
Lipids are used as energy.
What is Skeletal Hemopoiesis?
Red bone marrow produces :
*red blood cells (erythrocytes)
* white blood cells (leukocytes)
* platelets (thrombocytes)
5 Shapes of Bones?
- Long
- Short
- Flat
- Irregular
- Sesamoid
Describe a Long Bone?
Long – Are longer than they are wide.
* femur
* tibia
* humerus
Describe a Short Bone?
Short – Are nearly equal in length and width.
* carpals
* tarsals
* metacarpals
Describe a Flat Bone?
Flat – Thin & relatively broad ; large surface area for muscle attachment.
* sternum
* ribs
* scapula
Describe a Irregular Bone?
Irregular – Complex shapes/Rare.
* vertebrae
* sacrum
* skull
Describe a Sesamoid Bone?
Sesamoid – Small bones situated with tendons.
* patella
What is the Temporalis Muscle responsible for?
Helps close and move the lower jaw for chewing, biting, and mouth closure.
What is the Orbicularis Oris Muscle responsible for?
Controlling lip movements and facial expressions.
Where is the Orbicularis Oculi Muscle responsible for?
Controls eye closure, blinkingm and facial expressions.
Differences between Compact & Spongy Bone?
Compact :
* Dense
* Strong
* Outer Layer
Spongy :
* Porous
* Flexible
* Inner Layer
What are Intervertebral Disks and their function?
In between each vertebrae :
* absorbing shocks & facilitating movement
* enables smooth spinal movement
* maintains stability
What are True Ribs?
1 - 7 Pairs
What are False Ribs?
8 - 12 Pairs
What are Floating Ribs?
11 - 12 Pairs
Why are they called “floating” ribs?
Because they are not attached to the sternum, only to the vertebrae.
What are the 8 Carpal Bones in the Hand?
- Scaphoid
- Lunate
- Triquetrum
- Pisiform
- Trapezium
- Trapezoid
- Capitate
- Hamate
What are the 5 Metacarpal Bones in the hand?
- First
- Second
- Third
- Fourth
- FIfth
What are the 14 Phalange Bones in the hand?
~ Proximal phalanges (base of fingers) :
* 5 bones
~ Intermediate phalanges (middle of fingers) :
* 4 bones
~ Distal phalanges (tips of fingers) :
* 5 bones
What is the smallest bone in the human body?
Stapes bone – Located in the middle ear ; measuring approximately 3 millimeters in length.
What are 3 bones that differ in male and female?
- Pelvis
- Skull
- Sternum
What is the Appendicular Skeleton?
Forms the limbs and appendages, enabling movement and mobility.
Parts of Appendicular Skeleton?
- Scapula
- Clavicle
- Humerus
- Radius
- Ulna
- Carpals
- Metacarpals
- Phalanges
- Pelvic Girdle
- Femur
- Patella
- Tibia
- Fibula
- Tarsals
- Metatarsals
What is the Axial Skeleton?
Forms the body’s central axis, providing support and protection.
Parts of Axial Skeleton?
- Skull
- Sternum
- Rib Cage
- Mandible
- Vertebral Column
