a&p exam #2 Flashcards
definition of ossification
the formation of bone matrix
the hardening of soft tissue into bone
the process of laying down new bone material by osteoblast cells
begins 6th&7th week of embryonic development and continues until age 25
define osteopenia
a condition in which there is a lower than normal bone mass or bone mineral density
define osteoporosis
a condition in which there is a decrease in the amount & thickness of bone tissue
describe the steps of bone fracture
INFLAMMATORY STAGE: body sends special cells to injured area which causes area to become inflamed and then other cells form a hematoma around the broken bone
REPARATIVE STAGE: about a week after injury, a soft callus replaces the hematoma. over the next few weeks the callus becomes harder
REMODELING STAGE: around 6 weeks after injury, regular bone replaces hard callus.
dynamic movements of skeleton
FLEXION
EXTENTION
HYPEREXTENSION
ABDUCTION
ADDUCTION
types of fractures
TRANSVERSE FRACTURE: straight line break across bone
SPIRAL FRACTURE: spirals around bone
GREENSTICK FRACTURE: partial fracture (mostly in kids)
COMPRESSION FRACTURE: when bone gets crushed
POTTS FRACTURE: ankle fracture
DISPLACED FRACTURE: ends of bone out of alignment
EPIPHYSEAL FRACTURE: fracture that occurs where bone matrix is undergoing calcification/ chondrocytes are dying
COMMINUTED FRACTURE: bone shatters, many fragments
COLLES FRACTURE: break at distal portion of radius
describe the hormones that impact bone growth
GROWTH HORMONE: produced by pituitary gland and stimulates bone growth by stimulating protein synthesis and rate of cell division
THYROXINE: from thyroid gland, stimulates bone growth by stimulating cell metabolism & increasing rate of osteoblast activity
SEX HORMONES: stimulate osteoblasts to produce bone faster than epiphyseal cartilage expands which closes growth plates
PARATHYROID HORMONE: from parathyroid glands
CALCITONIN: from c cells of thyroid glands
relationship between calcitonin, calcitriol, PTH & how they maintain blood calcium levels
Calcitriol helps increase blood circulation levels and calcitonin helps decrease blood calcium levels.
Calcitriol participates with PTH to stimulate osteoclastic bone resorption
Calcitonin counteracts effects of PTH & Calcitriol
Nutritional needs and effects on bone
MINERALS: bones need source of calcium & phosphorus for normal growth
CALCITRIOL/VITAMIN D: essential for normal calcium & phosphorus absorption in digestive tract
VITAMIN C: required for certain enzymatic reactions in collagen synthesis, also stimulates osteoblast differentiation
VITAMIN A: stimulates osteoblast activity
VITAMIN K&B: helps with synthesis of protein in bone
remodeling/homeostatic mechanisms of the skeletal system
bone remodeling continuously recycles & renews organic 3 mineral components of bone matrix.
remodeling replaces the matrix
older mineral deposits are removed from bone & released into the circulation at the same time that circulating minerals are absorbed & deposited
involves osteoblasts and osteoclasts
regulates calcium homeostasis and repairing micro-damage to bones from everyday stress
functions of the skeletal system
SUPPORT
STORAGE OF MINERALS/LIPDS
BLOOD CELL PRODUCTION
PROTECTION
LEVERAGE
major cell types in bone and their functions
OSTEOCYTES: maintain protein & mineral content of surrounding matrix
OSTEOGENIC CELLS: maintain populations of osteoblasts $ repair fractures
OSTEOBLASTS: make & release proteins/organic components of the matrix
OSTEOCLASTS: absorbs & removes bone matrix
steps of endochondral ossification
STEP 1: mesenchymal cells differentiate into chondrocytes and form the cartilage model for bone
STEP 2: chondrocytes near center of cartilage model undergo hypertrophy & alter contents of the matrix they secrete which enables mineralization
STEP 3: chondrocytes undergo apoptosis due to decreased nutrient availability; blood vessels invade & bring osteogenic cells
STEP 4: primary ossification center forms in the diaphyseal region of periosteum, called the periosteal collar
STEP 5: secondary ossification centers develop in the epiphyseal region after birth
steps or intramembranous ossification
-begins when osteoblasts differentiate within fibrous connective tissue
-osteoblasts become entrapped by the osteoid that they secure, transforming them to osteocytes
-spongy bone and periosteum form
-compact bone forms superficially to the spongy bone
-blood vessels form the red marrow
cell types in bone
OSTEOGENIC CELLS: stem cells whose divisions produce osteoblasts
OSTEOBLASTS: immature bone cells, secrete organic compounds
OSTEOCYTES: mature bone cells, maintains bone matrix
OSTEOCLASTS: secretes acids & enzymes to dissolve bone matrix
sutural bone definition, shape, & example
a synarthrotic joint located between bones of skull. edges are interlocked together by dense fibrous connective tissue
SHAPE: small, flat & oddly shaped
EXAMPLE: found between flat bones of skull
bone structure of flat bone
one layer of spongy bone within two layers of compact bone surrounding the spongy bone
structure of long bone
spongy bone
compact bone
epiphysis (proximal and distal)
diaphysis
metaphysis
epiphyseal like
medullary cavity
yellow bone marrow
red bone marrow
endosteum
periosteum
articular cartilage
components of bone matrix
CALCIUM PHOSPHATE: 2/3 of bone weight (67%)
TYPE 1 COLLAGEN: (organic matter) 33%
calcium phosphate and calcium hydroxide form hydroxyapatite
sesamoid bone shape & example
SHAPE: small, round, and flat
EXAMPLE: near joints of knees, hands, & feet
(sesamoid patellae)
long bone shape & example
SHAPE: long and slender
EXAMPLE: arm & thigh
flat bone shape & example
SHAPE: thin parallel surfaces
EXAMPLE: form roof of skull & sternum
short bone shape & example
SHAPE: box like
EXAMPLE: carpal and tarsal bones
irregular bone shape & example
SHAPE: complex shapes with flat, short, notched or ridged surfaces
EXAMPLE: pelvis & vertebrae
ossification vs. calcification
ossification specifically means the conversion of connective tissue into bone tissue (is a process of laying down new bone material by osteoblasts)
calcification means the depositing of calcium salts that build up in soft tissue, causing it to harden
structure of periosteum & functions
STRUCTURE: membrane with a fibrous outer layer and cellular inner layer
FUNCTION: isolates the bone from surrounding tissues, provides a route for the blood vessels and nerves & takes part in bone growth & repair
structure of endosteum & function
STRUCTURE: incomplete cellular layer that lines the medullary cavity. covers trabeculae of spongy bone and lines inner surfaces of central canals of compact bone. Simple flattened layer of osteogenic cells that cover bone matrix
FUNCTION: causes bone growth, repair and remodeling
major parts of an osteon
CENTRAL CANAL: contains one or more blood vessels
PERFORATING CANAL: extend perpendicular to surface (transports nutrients to bone tissue)
LAMELLAE: forms series of nested cylinders around central canal (gives bone hardness and ridgity)
CANALICULI: small duct that interconnects the lacunae of osteons (provides routes for nutrients to reach osteocytes and wastes to leave osteocytes)
LACUNAE: small cavity in bone that encases osteocytes (provide home for cells in bone)
bone structure of compact vs. spongy bone
COMPACT: relatively solid, forms sturdy protective layer that surrounds medullary cavity (wall of diaphysis)
SPONGY: open network of struts and plates that resembles latticework (in epiphyses)
definition of calcification
a process in which calcium builds up in the body causing the tissue to harden
major types of joints
& functions
SYNOVIAL JOINT: highly mobile, allow for free movement
BALL & SOCKET JOINT: allows backwards, sideways, forward and rotating movement
SADDLE JOINT: allows two degree movement
CARTILAGINOUS JOINT: allows more movement between bones than fibrous joints but less than synovial joint
HINGE JOINT: allows flexion and extension in one plane
CONDYLOID JOINT: modified ball and socket joint that allows for flexion, extension, abduction and adduction
FIBROUS JOINT: provide protection for internal organs and weight bearing stability
PIVIOT JOINT:permits rotation around single axis (ex. wrist)
AMPHIARTHROSIS: allows small amounts of mobility
PLANE JOINT: allows for gliding movement
SYNARTHROSIS: immovable joint. provides strong connection between adjacent bones
define ossification
the process by which osteoblasts produce new bone matrix.
osteoblasts make & release proteins & other organic components of the matrix.
osteoblasts also help increase local concentrates of calcium phosphate above its solubility limit which triggers deposition of calcium salts into organic matrix.
before calcium salts are deposited, the organic matrix is called osteoid
process converts osteoid to bone.
osteocytes develop from osteoblasts that have become completely surrounded by bone matrix.
what is osteoarthritis
(degenerative joint disease)
generally effects those 60+ and may be from cumulative wear and tear at joints or genetic factors affecting collagen formation
what is rheumatoid arthritis
inflammatory condition that affects more woman than men
occurs when immune response mistakenly attacks joint tissue.
when body attacks own tissue and is known as an auto immune disease
what is gouty arthritis
crystals of uric acid form within the synovial fluid of joints.
accumulation eventually interferes with movement
the cause is unknown but is age related to change in articular cartilage
common synovial joint accessory structures and their function
MENSCI: pads of fibrocartilage between the bones in joints. menisci may subdivide synovial cavity, channel flow of synovial fluid or allow variations in shapes of articular surfaces
FAT PADS: localized masses of adipose tissue covered by synovial membrane. they protect articular cartilages & act as packing material for joints.
BURSAE: provide a gliding surface and a cushion for soft tissues
LIGAMENTS: strengthen and support the joint by anchoring the bones together and preventing their separation.
why is the elbow joint so stable?
it’s extremely stable because the bony surface of the humerus & ulna interlock
a single articular capsule surround both the humeroulnar & proximal radioulnar joints
strong ligaments reinforce the articular capsule
gliding movement at synovial joint
two surfaces sliding past one another.
occurs between surface or articulating carpal bones, tarsal bones, & between clavicles & the sternum.
can occur in any direction but only slight movement rotation is prevented by capsule & associated ligament
angular movement at synovial joint
Angular movements are produced when the angle between the bones of a joint changes.
flexion, extension, hyperextension, abduction, adduction and circumduction
flexion at synovial joint
movement in anterior-posterior plane that decreases angle between articulation bones
extension at synovial joints
occurs in the same plane but increases angle between articulating bones
major type of joints by structure
FIBROUS
CARTILAGINOUS
BONY: forms when fibrous of cartilaginous joints ossify
SYNOVIAL
basic structure of a synovial joint
two layer joint capsule surrounds synovial joint.
joint capsule contains inner synovial membrane & outer fibrous capsule
this membrane does not cover the articulating surfaces within joint
synovial membrane consists of areolar tissue covered by an incomplete epithelial layer
structure of fibrous joint
These joints are also called immovable joints because they do not move.
Fibrous joints have no joint cavity and are connected by fibrous connective tissue made of mainly collagen
The skull bones are connected by fibrous joints called sutures.
structure of cartilaginous joints
type of joint where the bones are entirely joined by cartilage, either hyaline cartilage or fibrocartilage.
These joints generally allow more movement than fibrous joints but less movement than synovial joints.
structural classification of synovial joints
HINGE: elbow
SADDLE: carpometacarpal joint
PLANAR: acromioclavicular joint
PIVIOT: atlantoaxial joint
CONDYLOID: metapophalangeal joint
BALL AND SOCKET: hip
definition of trochanter
a large proximal projection on a bone
4 different kind of projection bone markings
HEAD
FACET
CONDYLE
RAMUS
three kind of bone markings
depressions
elevations
tunnels
what are bone markings
points of muscle/tendon attachments that allow vessels and nerves through way and where other bones articulate
what is the bone marking where tendons and ligaments attach & where adjacent bones articulate(joints)
elevations
6 kind of depression and opening bone markings
MEATUS
SINUS
GROOVE
FISSURE
FORAMEN
FOSSA
a calcified skeletal muscle is an example of
heterotopic bone formation
what happens when levels of calcium ions are elevated in the blood
they stimulate the secretion of calcitonin hormone
protein-crystal interactions
allow bone to be strong, somewhat flexible and highly resistant to shattering
what is the most abundant cell type in bone
osteocytes
what does parathyroid hormone do
stimulates osteoclast activity
increases rate of calcium absorption
decreases rate of calcium excretion
raised blood calcium ion levels
what is a foramen
rounded passageway for passage of blood vessels/nerves
what is formed by intramembrabous ossification
FLAT BONES
the roof of skull
clavicle
what does intramembranous ossification begin with
differentiation of mesenchymal cells
important steps of endocondral ossification
Chondrocytes enlarge and the
surrounding matrix begins to calcify.
Enlarged chondrocytes die.
Blood vessels grow around the
edges of the cartilage.
Perichondrial cells become
osteoblasts and produce a
superficial layer of bone.
Osteoblasts replace calcified
cartilage with spongy bone.
where are osteogenic cells located
inner cellular layer of the periosteum
where does secondary ossification occur
in the epiphyses
cells that free calcium from bone to maintain blood calcium levels
osteoclasts
what are the joints between vertebrae
amphiathrosis
is a synovial membrane considered an accessory structure
NO
what is the medial surface of the knee reinforced by
tibial collateral
ligaments that limit the anterior/posterior movement of the tibia and maintain alignment of femoral and tobias condyles
cruciate
what kind of joints are intercarpal articulations
gliding joint
Syndesmosis is to ligament as
symphysis is to
fibrous cartilage
Dense fibrous connective tissue is to
a suture as a periodontal ligament is to
a(n)
gomphosis
definition of pronation
rolling the distal epiphysis of the radius over ulna
inward rotation of forearm
A ligamentous connection such as an
antebrachial interosseous membrane is
called a
syndesmosis
A joint where bones fuse together with
bone tissue is called
synostosis
The intervertebral disc joint is called
symphysis
Dense fibrous connective tissue is to
a suture as a periodontal ligament is to
a(n)
gomphosis
which is the mature bone cell
osteocytes
what is the parent of bone builder cells
osteogenic cells
which bone cell is the bone builder
osteoblasts
which bone cell is responsible for bone resorption
osteoclasts
which bone cell is stimulated by PTH
osteoclasts
which bone cell is inhibited by calcitonin
osteoclasts
who is the target when calcitonin is released
KIDNEY
INTERSTITIAL LINING
OSTEOCLASTS
OSTEOBLASTS
who’s the target when is PTH released
KIDNEY
OSTEOCLASTS
INTERSTITIAL LINING
which movement happens when moving from standing to sitting position
flexion at hip and knee joint
what movement happens when doing a full jumping jack
upstroke abduction at shoulder and hip
downstroke adduction at shoulder and hip
flexion and extension at knee for jumping
which movement happens when laying flat and doing a sit up
flexion at hip, knee and along spine
what movement happens when turning a door knob
flexion at shoulder
flexion at fingers
supination
SYNARTHROSIS JOINTS
(nearly immobile)
FIBROUS
suture
gomphosis
CARTILAGINOUS
synchondrosis
BONY FUSION
synostosis
gomphosis joints
fibrous connection plus insertion of alveolar processes
located between teeth and jaw
Synchondrosis
interposition of cartilage plate
example: epiphyseal cartilage
Synostosis
conversion of other articular form to a solid mass of bone
example: portions of skull,
bony fusion
Amphiarthrosis
(little movement)
FIBROUS
syndesmosis
CARTILAGINOUS
symphysis
syndesmosis
ligamentous connection
between tibia and fibula
symphysis
connection by fibrocartilage pad
example: intervertebral discs
diarthrosis
(free movement)
PLANES OF MOVEMENT
monaxial: movement @ one plane
ex. ankle
biaxial: movement @ 2 planes
ex. wrist
triaxial: movement in 3 planes
ex. shoulder
diarthrosis synovial
Complex joint bound by joint capsule containing synovial fluid
ex. ends of long bone
intramembranous ossification vs. endochondral ossification
in intramembranous ossification, bone develops directly from sheets of mesenchymal connective tissues. forms flat bones of the skull, clavicle and most cranial bones
in endochondral ossification, bone develops by replacing hyaline cartilage. form all long bones
BONES OF AXIAL SKELETON AND THEIR FUNCTIONS
80 BONES IN AXIAL SKELETON
SKULL(8 cranial& 14 facial):
protection & structure
6 OSSICLES:
transmission of sound waves
HYOID BONE:
carries weight of tongue
THORACIC CAGE(sternum & 24 ribs) :
*protects heart and lungs)
VERTEBRAL COLUMN (24 vertebrae, sacrum & coccyx)
protects and supports spinal cord
CRANIAL BONES
Frontal(1)
PARIETAL(2)
OCCIPITAL(1)
TEMPORAL(2)
SPHENOID(1)
ETHMOID(1)
8 cranial bones total
FACIAL BONES
NASAL(2)
LACRIMAL (2)
INFERIOR NASAL CONCHA (2)
MAXILLA(1)
MANDIBLE(1)
VOMER(1)
ZYGOMATIC (2)
PALATINE(1)
14 FACIAL BONES TOTAL
paranasal sinuses function
open into nasal cavity
lined with cells that make mucus
NASAL COMPLEX:
FRONTAL BONE
frontal sinuses
ETHMOID BONE
ethmoid sinus
NASAL BONE
MAXILLA
PALATINE BONE
SPHENOID
sphenoidal sinus
SUPERIOR NASAL CONCHA
MIDDLE NASAL CONCHA
INFERIOR NASAL CONCHA
maxillary sinus
structural differences of skull in infants vs adults
INFANT SKULL:
frontalle(where bone hasn’t fused together yet)
^covered by membrane to protect
ADULT SKULL:
have suture lines that show where the different skull bones have fused together.
spinal curvatures and their functions
PRIMARY CURVE DEVELOPS BEFORE BIRTH
SECONDARY AFTER BIRTH
CERVICAL CURVE: secondary curve, develops as infant learns to balance weight of its head on vertebrae of neck
THORACIC CURVE: primary curve, provides room for thoracic organs
LUMBAR CURVE: secondary curve, balances weight of trunk over lower limbs
SACRAL CURVE: primary curve, provides room for abdomiopelvic organs
VERTEBRAL REGIONS
CERVICAL(7) - small bodies
THORACIC(12) -thicker bodies than cervical(giraffe)
LUMBAR(5)-thickest bodies (moose)
SACRUM(5 fused)
COCCYX(4 fused)
significance of thoracic and rib articulations
maintains position of vertebral column, protects heart and lungs,
attachment point for muscles involved with breathing
APPENDICULAR SKELETON BONES
PELVIS
PECTORAL GIRDLE
HUMERUS
SCAPULA
CLAVICLE
CARPAL BONES
METACARPALS
PHALANX
RADIUS
ULNA
FIBULA
PATELLA
FEMUR
SACRUM
TIBIA
ILLUM
TARSALS
METATARSALS
ISCHIUM
ACROMION
CALCANEUS
bones that form pectoral girdle and their functions
clavicle: increased range of motion of shoulders away from body (acromial end and sternal end)
scapula: allows full functional upper extremity movement
bones of upper limb
HUMEUS:
RADIUS:
METACARPALS:
PHALANGES:
CARPALS:
BONES OF PELVIC GIRDLE
ilium
ischium
pubis
The main functions of the pelvic girdle are to transfer the weight of the upper body to the lower limbs when sitting or standing, and provide attachment points for muscles that help with locomotion and posture.
bones of lower limbs
TIBIA
FIBULA
TARSALS
FEMUR
The lower limb serves a vital role in locomotion, standing, and supporting our weight.
male vs female pelvis
MALE: adapted to fit more massive and sturdy body architecture. narrower pelvis that’s heavier and thicker
WOMAN: wider and broader pelvis with less prominent ischial spines and helps woman through pregnancy and childbirth
what can study of skeleton show about individual
changes in shape, size and density can indicate disease or trauma / unbalanced hormone and nutrients levels
skeletal differences between man and woman
male skulls are heavier and bone is thicker. muscle attachment is more defined than females
females have longer torsos to accommodate the reproductive organs
aging process on skeletal system
bones become more brittle and break easier due to loss of collagen, decrease in production of growth hormone, calcium & decrease in protein synthesis
basic structure of synovial joint
the ends of bones are encased in smooth articular cartilage.
Together, they are protected by a joint capsule lined with a synovial membrane that produces synovial fluid.
The capsule and fluid protect the cartilage, muscles, and connective tissues.
articulations between vertebrae of the verbretal column
The articulating surfaces of adjacent vertebral bodies attach to each other by intervertebral discs in addition to numerous ligaments.
