Bones and Skeletal Tissues
Name the 3 types of skeletal cartilege
hyaline, elastic and fibrocartiledge
skeletal cartilage has lots of blood vessels and nerves
false. it has none
skeletal cartilage is surrounded by _________ (dense regular CT) that resists outward expansion like a girdle
what is skeletal tissue primarily made of that accounts for it's resilience and allows it to spring back after being compressed?
list the 4 types of hyaline cartiledge
what is the function of the articular cartilage?
covers the ends of long bones?
what is the function of the costal cartilage?
connects the ribs to the sternum
what is the function of the respiratory cartilage?
makes up the larynx and reinforces air passages
what is the function of the nasal cartilage?
supports the nose
what are the 2 regions of the body where elastic cartilage is found?
the external ear and the epiglottis
name the 2 places where fibrocartilage is found
menisci of the knee
which bones make up the axial skeleton and what is it's function?
the axial skeleton includes the bones of the skull, vertebral column and rib cage and is involved in protecting, supporting and carrying other body parts
which bones make up the appendicular skeleton and what is it's function?
the appendicular skeleton consists of the bones of the upper and lower limbs, shoulder and hip and helps up move around and manipulate our environment
define "long bones"
longer than they are wide (e.g. the humerus)
_____________ are cube shaped bones of the wrist and ankle that form within tendons (e.g. the patella)
these types of bones are thin, flattened and a bit curved (e.g. the sternum and most skull bones)
what is the definition of an irregular bone?
bones with a complicated shape
(vertebrae and hip bones)
list the 5 functions of bones
4. mineral storage
5. blood cell formation
list he 4 different types of bones
what is the name of the dense outer layer of bones whose core is filled with yellow bone marrow in adults? (red in babies)
define the spongy bone
a honeycomb of trabeculae (little beams) whose open spaces are typically filled with yellow or red marrow
what is the long bone shaft called?
what are the ends of a long bone called? (these ends are often broader than the diaphysis)
bone markings are bulges, depressions and holes what serve as...(3 functions)
1. sites of attachment for muscles ligaments and tendons
2. joint surfaces
3. opening (conduits) for blood vessels and nerves
projections are bone marking that_______ _________
list the 4 types of projections
1. tuberosity - rounded projection
2. crest - narrow prominent ridge of bone
2. trochanter - large, blunt, irregular surface
4. line - narrow ridge of bone
what is a tubercle
it's a small, rounded projection
what is a condyle
it's a raised area above a condyle (a projection - sites of muscle and ligament attachment)
a sharp, slender projection
any bony prominence (a projection)
list the 4 projections that help for form joints
1. head - bony expansion carried on a narrow neck
2. faucet - smooth, nearly flat, articular surface
3. condyle - rounded articular projection
4. ramus - armlike bar of bone
list the six bone markings that are classified as depressions and openings
1. meatus - canal-like passageway
2. sinus - cavity within a bone
3. fossa - shallow, basin-like depression
4. groove - furrow
5. fissure - narrow, slitlike opening
6. foramen - round or oval opening through a bone
what are the 3 functional zones involved in long bone growth?
1. growth zone
2. transformation zone
3. osteogenic zone
the function of the growth zone is...?
cartilage cells undergo mitosis, pushing the epiphysis away form the diaphysis
describe the function of the transformation zone
older cells enlarge, the matrix becomes calcified, cartilage cells die and the matrix begins to deteriorate
define osteogenic zone
new bone formation occurs
cartilage continually ________ and is _________ by bone
when bone is added and resorbed it's known as
during infancy and childhood _______________ is stimulated by ____________
epiphyseal plate activity/growth hormone
what are the 3 functions of testosterone and estrogen during puberty?
1. promote growth spurts
2. cause masculinization and feminization of specific parts of the skeleton
3. induce epiphyseal plate closure - ending longitudinal bone growth
bone remodeling consists of ___________ (2 things)
bone deposit and bone resorption
spongy bone is replaced
every 3- 4 years
compact bone is replaced
every 10 years
what are the 2 remodeling units? (the bone builders and bone breakers)
osteoblasts and osteoclasts
_____________ occurs where bone is injured or added strength is needed
what requires a diet rich in protein, vitamins C,D and A, calcium, phosphorus, magnesium and manganese
what are the 2 things that osteoclasts secrete?
1. lysosomal enzymes - they digest organic matrix
2. acids - they convert calcium salts into soluble forms
list the 5 reasons calcium is necessary
1. transmission of nerve impluses
2. muscle contraction
3. blood coagulation
4. secretion by glands and nerve cells
5. cell division
how are bone fractures classified?
1. the position of the bone after the fracture
2. completeness of the break
3. the orientation of the bone to the long axis
4. whether or not the bone ends penetrate the skin
define a compression fracture
when the bone is crushed, common in porous bones
define a depressed fracture
when a broken bone portion is pressed inward, a typical skull fracture
what is an incomplete fracture called (when one end of the bone breaks and the other end bends - common in children)?
define a spiral fracture
a ragged break when the bone is excessively twisted - common in sports injuries
list the 4 fracture classifications
define an incomplete fracture
when the bone is not broken all the way through
define a complete fracture
when the bone is broken all the way through
define a displaced fracture
when the bone ends are out of normal alignment
define a non-displaced fracturte
when the bone ends retain their normal position
when the fracture is parallel to the long axis of the bone it's called...?
a linear fracture
a fracture perpendicular to the long axis of the bone (a break along the cross section)
when the bone ends penetrate the skin
a compound (open) fracture
when bone ends do not penetrate the skin
a simple (closed) fracture
a comminuted fracture is when
the bone fragments into 3 or more pieces (common in the elderly)
an epiphyseal fracture is...
when the epiphysis separates from the diaphysis along the epiphyseal line - occurs where cartilage cells are dying
list the 4 steps involved in healing a fracture
1. a hematoma forms
2. fibrocartilaginous callus forms
3. bony callus forms
4. bone remodeling occurs
bones are inadequately mineralized causing softened weakened bones
main symptom is pain when weight is applied
caused by insufficient calcium or vitamin D deficiency
bones of children inadequately mineralized causing softened weakened bones
bowed legs and deformities of the pelvis, skull and rib cage are common
caused by insufficient calcium or vitamin D deficiency
a group of diseases in which the rate of reabsorption exceeds the rate of bone deposit - spine is most vulnerable
occurs often in postmenopausal women
treatment of osteoporosis
calcium and vitamin D supplements
increased weigth bearing exercise
hormone replacement therapy
hrt controversial because
it increases the risk of heart attack, stroke and breast cancer
hrt is frustrating because
it does not reverse osteoporosis, merely slows it
things that cause bone loss
caffeine calorie restriction
alcohol low body weight
excess animal protein medications