Unit 2 - The Skeletal System Flashcards
Five functions of skeletal system
Support Protection Movement Mineral storage Hematopoiesis (blood cell formation)
Bone shapes
Long bones Short bones Flat bones Irregular bones Round bones
Osteoprogenitor cells
These multiply and can differentiate into osteoblast cells when needed to form new bone
Osteoblasts
Bone forming cells
Secrete the collagen snd other organic components that make up the matrix part of bone
Osteoclasts
Help break down bone snd add calcium and phosphates ti the blood (resorption)
Growth snd repair tissue
Osteocytes
Mature cells that come from osteoblasts
Found in cavities called lacunae
Compact bone
Dense osseous tissue located in the superficial surface
Osteons (compact bone)
Give bone great strength in one direction
Central canal (compact bone)
Center area of compact bine is where the blood vessels are found
Canaliculi (compact bone)
Microscopic canals between the lucanae
Osteocytes are found here
Lamellae (compact bone)
Layers of matrix or hydroxyapatite (made of calcium and phosphate) provides strength
Spongy bone tissue
An open network of osseous tissue located deep inside the bone
Trabeculae (soft bone tissue)
Bony spicules running different directions inside the bone
What are the spaces in the trabeculae filled with?
Bone marrow
Diaphysis shaft
Long bone
Thick layer of superficial compact bone
Filled with yellow bone marrow
Epiphysis ends
Long bone ends
Articular cartilage covers this end and a band called the epiphyseal plate “aka growth plate”
Membranes (2 types)
Long bone
Periosteum: dense fibrous connective tissue wrapping around bone
Endosteum: connective tissue lining the inside of bone
Marrow hematopoiesis
Long bone
Bone marrow fills the medullary cavity in the middle of the bone
Adipose tissue which gives the tissue its yellow color
Intramembranous ossification
The way flat bones of the skull and most of the clavicle are formed
Develops between layers of fibrous connective tissue
Endochodral ossification
Most bones in the skeleton are developed by this
Three stages of endochondral ossification
Bony collar formation
Primary ossification center formation
Secondary ossification centers formation
Appositional growth
Bone increases in the thickness or width
Strengthens bone and occurs in mature bone
Endochondral growth
Interstitial growth increases the length of long bone
Chondrocytes undergo mitosis on epiphyseal side of plate
Frontal bone
Skull
Single slightly curved flat bone (forehead)
Parietal bones
Skull
Paired bones are slightly curved flat bones (top of skull)
Temporal bones (2)
Skull
Lateral and inferior base of cranium
External auditory meatus
Temporal bones in skull
Tube forming the ear canal
Styloid process
Temporal bones : Skull
Needle like projection of bone found on the base of the temporal loan
Mastoid process
Temporal bones : skull
Large round projection on the inferior lateral aspect of temporal bone
Occipital bone
Posterior inferior base of the cranium snd contains several important structure
Occipital condyles
Occipital bone: skull
Posterior inferior base of cranium
Structure that allows the head and neck to nod yes
Foramen magnum
Occipital: skull
Large hole in the occipital bone
Sphenoid bone
Butterfly or bat shaped bone constitutes much of the anterior inferior cranial floor
Sella turcica
Skull
Center in of the sphenoid bone
Ethmoid bone
Cube shaped bone located anterior to the sphenoid bone and behind the nasal bone
Contains crista galli and cribiform plate
Maxillae
Upper jaw bone
Pair of bones fused together in the center of the face
Palatine bones
Bones fuse together to form the posterior hard palate in the roof of the mouth
Zygomatic bones
Cheekbones (and sides of eye orbits)
Nasal bones
Paired nasal bones comprise the bridge of the nose
Mandible
Lower jaw bone is moveable from the skull
Contains sockets holding the teeth
Hyoid bone
Small u-shaped bone embedded in the fleshy area between the mandible
Vertabrae
32-33 vertebrae
Each component has the same body and vertebral arch
Cervical vertebrae
Superior 7 vertebrae with an anterior convex curve
1: Atlas
2: Axis
Thoracic vertebrae
The 12 vertebrae form a posterior concave curve in the back of the thoracic cavity
Lumbar vertebrae
5 lumbar vertebrae form an anterior convex curve
Sacrum
5 vertebrae form posterior concave curve in the posterior wall of pelvic cavity
Coccyx
3-4 vertebrae form an anterior convex curve
Sternum
Breastbone
Ribs
12 pairs of ribs curved flat bones
7 true superior ribs
5 inferior ribs
2 floating ribs
Pectoral girdle and upper limb
Shoulder joint composed if the clavicle and scapula
Clavicle
Collar bone (curved)
Scapulae
Irregular shaped triangular, fat bone just posterior of the rib cage
Humerus
Single large long bone of upper arm
Radius
Long bone of the forearm
Ulna
Medial long bone of the forearm
Trochlea of the humerus
Carpals
8 per hand
Metacarpals
5 per hand
Phalanges
14 per hand (long bones in fingers)
Pelvic girdle and lower limb
hip joint composed of ox coxae
Supports entire eight of the upper body ina. Standing position
Ilium
Large flared superior bone of the os coxae
Ischium
Inferior portion of the coxal bone comprising the lateral portion of the pelvic inlet
Pubis
Anterior portion of the os coxae
Femur
Single large long bone of the thigh
Head and greater trochanter
Tibia
Medial large long bone of the lower leg
Head, tibial tuberosity and medial malleolus
Fibula
Lateral thin long bone of the lower leg
Tarsals
7 short bones of the ankle
Contains calcaneus
Metatarsals
Long bones comprising the fleshy part if the foot
Phalanges
Long bones of the toes
4 little toes have 3 and bug toe only has 2
Osteoporosis
Caused by a decreased bone density level
Articulations
Joints: Located where two or more bones join together
Two types of joints
Synathroses, amphiarthroses and diarthroses
Synathroses
Immovable joints located in the axial skeleton
Amphiarthroses
Slightly moveable joints located in the axial skeleton
Diarthroses
Freely moveable joints located in appendicular skeleton
Cartilage as shock absorber Fibrous connective tissue Joint cavity Ligaments Tendons Synovial fluid Bursae
Six Types of synovial joints
Plane Saddle Hinge Pivot Ball and socket Ellipsoid
Flexion
Decreased joint angle
Bending the joint
Extension
Increased joint angle
Bending to increase angle
Adduction
Toward midline
Abduction
Away from midline
Circumduction
Wide circle
Rotation
Axial movement around a point
Ex: turning head
Elevation
Up
Depression
Down
Dorsiflexion
Reduces the joint angle at the ankle and raises the toes
Plantar flexion
Increases the join angle at the ankle and pointing toes or going up in the balls of your feet
Eversion
Sole outward
Inversion
Sole inward
Pronation
Palms down
Supination
Palms up
Opposition
Unique feature of the thumb as it crosses the palm
Connective tissues
Muscles are attached to bone vis chords or sheets if dense fibrous connective tissue
Endomysium
Tissue around each individual muscle cell or fiber
Perimysium
Tissue around bundles of muscle cells
Each bundle muscle cells called fascicle
Epimysium
Tissue wrapped around the entire muscle
Osteoarthritis
Destruction if cartilage between bones in the synovial joint s
Rheumatoid arthritis
Persistent inflammation in the synovial joints
Fractures
Broken bones, several types
Kyphosis
Hunchback
Lordosis
Swayback (curve inward in lower back)
Osteogenesis imperfecta
Causes extremely fragile bones
Brittle bone disease
Osteosarcoma
Bone cancer
Seen in young individuals 10-25
Pagets disease
Causes bones to grow larger and weaker than normal
Bones might break more easily
Scoliosis
Causes lateral curve of the vertebral column