The Skeletal System Flashcards
What are the functions of the skeletal system
-To support the body
-To facilitate movement by being attachment points for muscles
-To act as levers for joints which serve as fulcrums
-To protect internal organs from injury
-To serve as a reservoir for a number of important minerals
-To act as a site for fat storage
What is hematopoiesis?
The production of blood cells in the red marrow
How many groups of classes are the 206 bones of the body divided into?
5 groups of classes
What shape are the long bones class of bones?
-Cylindrical
-Longer than they are wide
Where are long bones found in the human body.
-The arms(humerus, ulna,radius)
-The legs(Femur, Tibia, Fibula)
-The fingers(Phalanges, Metacarpals)
-The toes(Phalanges, Metatarsals)
What is the function of long bones?
They act as levers; they move when muscles contract
What is the shape of short bones?
-Cube like in shape
-Equal in length, width, and thickness
Where are short bones found in the human body?
-Tarsals of ankles
-Carpals of wrists
What is the function of short bones?
-They provide stability and support
-They have limited motion
What is the shape of flat bones?
-Thin
-Typically curved
Where are flat bones found in the human body?
-Cranial(Skull)
-Scapulae(Shoulder blades)
-Sternum(breastbone)
-Ribs
What is the function of the flat bones?
-They served as points of attachment for muscles
-They protect internal organs
What is the shape of irregular bones?
They do not have an easily characterized shape
Where are irregular bones found in the human body?
-The vertebrae
-Many facial bones
What is the function of irregular bones?
The vertebrae support the spinal cord and protect it from compressive forces
What is the shape of sesamoid bones?
-Small
-Round
-Sesame seed shaped
Where are sesamoid bones found in the human body?
-They are found in the tendons
What is unique about sesamoid bones in every human?
-they differ in number and placement from person to person
What is the one sesamoid bone found in everyone?
The patella
What is the function of sesamoid bones?
Protect the tendons from wear and tear
What 2 parts make up long bones?
-Epiphysis
-Diaphysis
What is the hollow region of the diaphysis called?
The medullary cavity
What is the medullary cavity filled with?
Yellow Marrow
What are the walls of the diaphysis composed of?
Compact bone
What is the wide section at the end of each bone called?
The epiphysis
What is the epiphysis filled with?
Spongy red bone marrow
Where does each epiphysis meet the diaphysis?
It meets the diaphysis at the metaphysis
What is the metaphysis?
It is a narrow area that contains the epiphyseal plate
What is the epiphyseal plate?
It is a layer of hyaline cartilage in a growing bone
What happens to the epiphyseal plate when the bone stops growing in adulthood?
The epiphyseal hardens and becomes osseus tissue and the epiphyseal plate becomes the epiphyseal line
What is the lining of the medullary cavity called?
The endosteum
What happens in the endosteum?
It is the area where bone growth , repair and remodeling occur
What is the outer surface of the bone covered with?
A fibrous membrane called the periosteum
What does the periosteum contain?
It contains blood vessels, nerves, and lymphatic vessels that nourish the compact bone
Where do tendons and ligaments attach to bones?
The periosteum
What surface does the periosteum cover?
It covers the entire bone outer surface area except where the epiphyses meet other bones to form joints
What are epiphysis covered by?
They are covered by articular cartilage
What is the function of the articular cartilage?
It acts as a shock absorber
What is the anatomy of a flat bone?
-Top layer of compact bone
-Middle layer of diploe (spongy bone)
-Bottom layer of compact bone
What is the purpose of flat bone anatomy?
If the outer layer (top layer of compact bone) of bone fractures, the brain is still protected by the inner(bottom layer of compact bone) layer.
What are bone markings?
The different surface features of bones that vary depending on function and location
What are the three different classes of bone markings?
-Articulations
-Projections
-Holes
What is an articulation class bone marking?
Articulation is where two bone surfaces come together (articulus = joint)
What is the physical description of articulate class bone markings?
Surfaces tend to conform to one another such as one being rounded and the other being cupped
What is a projection type bone marking?
A projection is an area of a bone that projects above the surface of the bone
What are the physical characteristics of projection bones?
These bones are attachments points for tendons and ligaments. Size and shape are indications of the forces exerted through the attachment to the bone.
What is a hole type bone marking?
An opening or groove in a bone that allows blood vessels and nerves to enter the bone.
What are the physical characteristics of hole type bone markings?
Size and shape reflect the size of the vessels and nerves that penetrate the bone at these points.
Which bones in the human are articulate type bone markings?
-Head(prominent rounded surface like head of femur)
-Facet(flat surface where synovial joints connect vertebrae to the spine)
-Condyles(Rounded knobs like femur condyles or occipital condyles)
-Knee Joint
Which types of bones have projection markings?
-protuberance(chin)
-process(transverse process of vertebrae)
-spine(ischial spine)
-tubercle(tubercle of humerus)
-tuberosity(deltoid tuberosity)
-line(temporal lines of the parietal bone)
-crest(iliac crest)
What bones have hole bone markings?
-Fossa(mandibular fossa)
-Fovea(fovea capitis on the head of the femur)
-Sulcus(sigmoid sulcus of the temporal bones)
-Canal(auditory canal)
-Fissure(auricular fissure)
-Foramen(foramen magnum in the occipital bone)
-Meatus(external auditory meatus)
-Sinus(nasal sinus)
What two materials is the skeletal system a reservoir for?
It is a reservoir for calcium and phosphorus
Why are calcium and phosphorus stored in the bones?
The bones play an important role in calcium homeostasis, they maintain the balance of these substances in the body. They bones provide rapid turnover of these substances when needed
What type of blood cells does the red marrow produce?
It produces erythrocytes (red blood cells)
It also produces leukocytes(white blood cells)
What type of cells does yellow marrow produce?
It produces adipocytes(fat cells)
What are osteoblasts?
Osteoblasts are specialized cells responsible for bone formation
What are osteogenic cells?
They are the stem cell precursor to osteoblasts and osteocytes
What are osteoclasts?
Osteoclasts are large cells that breaks down bone tissue
What does the fibrous outer layer of the periosteum composed of?
It is composed of collagen
What is the outer most layer of compact bone?
Circumferential Lamellae
In what direction do circumferential lamellae run in comparison to the bones surface? Why?
They run parallel to the bone’s surface.
They provide additional strength and resistance against twisting forces.
What is the periosteal artery?
It is the blood vessel supplying the periosteum and outer bone layers
What is the periosteal vein?
The periosteal vein drains blood from the outer layers of the bone and the periosteum
What are interstitial lamellae?
They are irregularly shaped bony plates that fill in the spaces between osteons in compact bone.
What are perforating canals/Volkmann’s canals?
They are microscopic channels in the bones that allow blood vessels to enter the bone from the periosteum.
What are perforating canals/Volkmann’s canals?
They are microscopic channels in the bones that allow blood vessels to enter the bone from the periosteum.
What is the central canal/haversian canal?
It is the central channel of an osteon carrying blood vessels and nerves.
What are concentric lamellae?
They are concentric layers of bone surrounding the central canal in an osteon
What is an osteon/haversian system?
It is the primary structural unit of compact bone. It consists of concentric lamellae surrounding a central canal
What are trabeculae?
They are the thin columns and plates of bone that create a spongy structure in cancellous bone.
How many bones make up the facial portion of the skull?
14
What do we call the group of bones that protect organs in the chest?
Thoracic cage
What is another name for the breastbone?
The sternum
What is another name for the breastbone?
The sternum
What is the appendicular skeleton?
The appendicular skeleton refers to the limbs, pelvis and shoulder bones
What is the bone framework that supports the upper limbs?
The pectoral girdle
What does the pectoral girdle consist of?
It consists of the clavicle and the scapula.
What is the function of the pelvic girdle?
The pelvic girdle connects the upper limbs to the axial skeleton and it enables arm movements and provides an attachment point for muscles
What is the name of the long bone between the scapula and sternum?
The clavicle
What is the name for the flat, triangular bone on the back that connects the clavicle and humerus?
It is called the scapula
How far does the upper limb stretch?
It stretches from the shoulder to the hands
How many bones make up the carpals in the wrist?
8 bones
How many bones make up the tarsals in the ankles.
7 bones
How are the bones of the carpals arranged in the wrist?
They are arranged in 2 rows
What is the function of the tarsals in the ankle?
They allow for foot movements and support body weight
How many bones make up the metatarsal bones in the feet?
5 long bones
What is the function of the metatarsal bones on the feet?
-They form the foot’s arch and enable movements like jumping, running. -They provide structural support and flexibility
What is the bone structure that connects the spine to the legs?
The pelvic girdle
What bones make up the pelvic girdle?
-The hip bones
-Sacrum
-Coccyx
What is the function of the pelvic girdle?
-Provides support for internal organs
-Facilitates movement like walking and sitting
What is the brain case?
The brain case is the bony structure that protects the brain
What is the coronal suture?
It is a joint connecting the frontal and parietal bones
What is the shape of the coronal suture?
It is a fibrous, joint that runs horizontally across the skull separating the frontal and parietal regions
What is the smooth area between eyebrows and above the nasal bridge called?
It is called the glabella
What is the bone that forms the forehead and upper eye sockets called ?
It is called the frontal bone
What is the purpose of the frontal bone of the skull?
It protects the brain’s frontal lobes
What is the large bone that forms the roof and sides of the skull?
The parietal bone
What is the opening above the eye for blood vessels and nerves?
The supraorbital foramen
What is the supraorbital margin?
It is a prominent ridge located above the eye socket.
What is the function of the supraorbital margin?
-It offers structural support for the eye -It is an attachment point for several facial muscles
What is the eye socket that holds the eye called?
It is called the orbit
What is the purpose of the eye orbit?
-It provides protection
-it provides optimal position for vision