Lecture Exam #2: Skeletal And Bone Features Flashcards
What is a part of the axial skeleton?
Skull, vertebrae, sternum, ribs, sacrum, hyoid
What is part of the appendicular skeleton?
Pectoral girdle, upper/lower limbs, pelvic girdle
What is articulation?
Consisting of segments united by joints
Auditory ossicles (SKULL)
3 in each ear in the middle: malleus, incus, stapes
Hyoid Bone:
Between chin & larynx, doesn’t articulate w/ any bone, suspended by muscle
Infant Skull
Fontanels: spaces between unfused bones
Metopic Suture: fusing of the frontal bones
Reaches full size by 8 or 9
Spine Vertebraes
33 TOTAL
Cervical: 7
Thoracic: 12
Lumbar: 5
Sacral: 5
Coccygeal: 4
Functions of Spine
-supports skull/trunk
-allows movement
-protects spinal cord
-absorbs stress
-provides attachment for limbs, thoracic cage, postural muscles
Types of Curvature:
- Newborn Curvature: C shape (thoracic/lumbar)
- Adult Curvature: S shape (cervical/pelvic)
- Abnormal Curvature: scoliosis, kyphosis, lordosis
Explain Scolosis
Abnormal lateral curvature in thoracic region, particularly in adolescent girls
Explain Kyphosis
Exaggerated thoracic curvature, caused by wrestling/weightlifting in young boys (hunchback)
Explain Lordosis
Exaggerated lumbar curvature, caused by pregnancy/obesity (sway back)
When you go down the spine vertebrae get…..
Larger
C1-ATLAS
supports head, has no body, allows yes nodding motion
C2-AXIS
dens projects into atlas, allows “no” nodding motion
Intervertebral Discs
binds vertebra, supports weight of body, absorbs shock
intervertebral foramen
holes seen from lateral views when vertebrae are connected, passage way for spinal nerves
vertebral foramen
hole in between body and spinous process
describe cervical vertebrae
bifid spinous process, only type with transverse foramen
describe a thoracic vertebrae 
spinous process is angled down and pointy, has costal facets for ribs
Describe the thoracic cage
has sternum/ribs/thoracic vertebrae, costal margin: downward arc of the ribs
what are the true ribs
ribs 1-7, direct attachment to dternum
what are the false ribs
ribs 8-10, join together then go to sternum
what are the floating ribs
ribs 11/12, still false, don’t attach at all
Describe the lumbar vertebrae
thick/stout body, blunt squarish spinous process
Compare male and female pelvis
male has a more narrow pelvic brim and pubic arch is 90° while a female has a wide pelvic brim in the pubic arch is 120° for childbirth
What are the four shapes of bones and give examples of each
Long: femur, short: talus, Flat: sternum, irregular: vertebra
 explain the parts of compact bone
osteon: Basic structural, concentric lamellae: Layers of matrix around central canals,
Perforating canals: Diagonal passages coming off the central canal
Nutrient foramina on surface
circumferential lamellae: Boundaries of dense bone
Interstitial lamellae: Remains of old osteons that broke down as bone grew & remodeled
explain the medullary (marrow) cavity
hollow part of bone that contains bone marrow
explain the makeup of spongy (cancellous) bone
spicules: slivers of bone
trabeculae: thin plates of bone
- red bone marrow fills spaces
- few osteons
- no central canals
what is the diaphysis on a bone
Cylinder of compact bone called the shaft
what is the epiphysis on a bone
end parts of bone that are separated by epiphyseal plates until fully connected to shaft when plate turns into line
where is articular cartilage on a bone what does it do
covers the epiphysis and creates joints when bones connect
what is periosteum
external sheath that covers bone, outer fibrous layer of collagen with inner osteogenic layer of bone forming cells
What is the epiphyseal plate
Area of hyaline cartilage that separates marrow spaces of epiphysis and diaphysis, AKA growth plate, transition zone where cartilage is replaced by bone (metaphysis)
what is the endosteum
thin layer of reticular connective tissue lining the marrow cavity
what is nutrient foramina
little holes on surface that allows blood vessels and nerves to enter the bone 
What’s the function of osteogenic cells
stem cells that differentiate and become osteoblasts
What is the function of osteoblasts
bone forming cells that line up as a single layer of cells under the endosteum and periosteum that then turn into osteocytes
what is the function of osteocytes
osteoblasts that form the lacunae (matrix cocoon),
- maintains bone matrix
- When stressed they send signals for aged bone remodeling
What is the function of osteoclasts

bone dissolving cells found on the bone surface, remodels
What does the matrix consist of
1/3 organic matter (synthesized by osteoblasts, collagen/carbohydrate/protein complexes)
2/3 inorganic matter (85% hydroxyapatite, 10% calcium carbonate, other minerals)
What is rickets
soft bones due to deficiency of calcium salts (more organic than inorganic matter)
What is osteogenesis imperfecta
excessive brittle bones due to lack of protein/collagen (more inorganic than organic matter)
What makes spongy bone different from compact bone
-spongy is made up of trabeculae, fills inner layer of bone, on the ends of bones
-Compact bone is made up of osteons, Fills outer layer of bone, on the shaft of bones
What is red marrow
hemopoietic tissue, found a nearly every bone in a child but in adult is found in skull/vertebrae/ribs/sternum/pelvic girdle heads of humerus and femur
What is the yellow marrow
found only in adults, red marrow turned into yellow fatty marrow, does not produce blood
What is ossification/osteogenesis
Formation of bone
what is intramembranous ossification
produces flat bones of the skull in most of the clavicle, Mesenchyme cells differentiate into osteogenic cells which then differentiate into osteoblasts which continue to deposit minerals
Mesenchyme cells also turn into trabeculae to create osteoid tissues
differentiation of spongy bone, compact bone, & medullary cavity
what is endochondral ossification
process in which bone develops from pre-existing cartilage
mesenchyme differentiates into hyaline cartilage then is covered with fibrous perichondrium which turns into chondrocytes then osteoclasts that form a bony collar around the middle of the cartilage the outside perichondrium turns into the periosteum 
primary ossification center: middle of the bone
explain metaphysis
once the diaphysis (primary ossification center) is formed metaphysis starts to occur
-osteoclasts break down cartilage which creates the hollow in the same process occurs
Interstitial growth
Bone increase in length
Appositional growth
bone increase in width 
wolff’s law of bone
REMODELING: collaborative and precise action of osteoblast and osteoclasts
-bone adapts to withstand stresses
achondroplastic dwarfism
Long bones stop growing in childhood, failure of cartilage growth in metastasis
-normal torso/short limbs
pituitary dwarfism
lack of growth hormone, normal proportions with short stature
What are the two main layers of the skin
Epidermis and dermis
What are the functions of the skin
resist trauma and infection, barrier functions, vitamin D synthesis, transdermal absorption, thermal regulation, sensation
Differences between epidermis and dermis
epidermis is an outer thin layer of the skin that has no blood vessels or nerves while the dermis is the thickest layer of skin & has nerves and blood capillaries
Five type of cells in the epidermis
stem cells & melanocytes (found in basale), keratinocytes (majority of cells), tactile (touch receptors), dendritic (macrophages in spinosum)
Five layers of the epidermis
stratum corneum, Stratum lucidum, stratum granulosum, stratum spinosum, stratum basale 
Which epidermal layer only seen in thick skin
stratum lucidum
what cells are in the stratum basale
melanocytes/tactical cells/stem cells/keratinocytes
what occurs in the stratum basale
Cell division, older cells are pushed into spinosum layer
What cells are in the stratum Spinosum
(several layers) keratinocytes & dendritic cells
what occurs in the stratum Spinosum
start of keratinization
What cells are in stratum granulosum
keratinocytes (3-5 layers)
What occurs in stratum granulosum
keratinocytes lose organelles & accumulate keratohyalin granules which then turn into fillagrin (basically where they prepare to die)
What cells are in the stratum lucidum
keratinocytes
What occurs in the stratum lucidum
The dead and flatten keratinocytes are densely packed with eleidin (makes them translucent)
What cells are in the stratum corneum
up to 30 layers of Dead scaly keratinized cells
What occurs in the stratum corneum
surface of cells flake off, layers help resist abrasion, penetration, and water loss (overall protection) 
Average life cycle of keratinocytes
30-40 days
What is the epidermal water barrier
consist of lipids/tight junctions/ thick layer of insoluble protein, the barrier cuts off cells from nutrients below & any dead cells exfoliate (dander)
Where is the epidermal water barrier located
between stratum granulosum and stratum Spinosum
What are the layers of the dermis
Dermal Papillae: upward finger like extensions
Papillary: superficial zone of dermis (thin zone of areolar tissue in & near dermal papilla)
Reticular: deeper & much thicker layer (dense irregular connective tissue) *stretchmarks
What are the structures of the dermis
collagen with elastic fibers, reticular fibers, fibroblasts, adipose tissue
- well supplied w blood vessels/glands/nerves
What are the functions of the dermis
protection, cushion deep structures from injury , provide nutrients for epidermis
Hypodermis
Made of more areolar & adipose tissue the dermis, has subcutaneous tissue & fat, pads body, highly vascular, bind skin to underlying tissues, drugs introduced by injection
What is subcutaneous tissue
hypodermis
What is subcutaneous fat
energy Reservoir, thermal insulation, Thicker in women
What factors give skin its color
Amount of melanin/hemoglobin/carotene & exposure to UV
Abnormal skin colors
Cyanosis: blueness (lack of oxygen)
Erythema: redness (body temp rises)
Pallor: paleness (anemic/cold)
Albinism: lack of pigment (inherited genes)
Jaundice: yellowness (bad liver)
Hematoma: bruise (clotted blood)
What creates fingerprints (friction ridges)
Markings on the fingertips that leave oily fingerprints on surface we touch
Flexion line
Lines on the flexor surfaces of the digits, palms, wrist, elbows
Freckles/moles
Tan to black aggregations of melanocytes
Hemangiomas
Patches of discolored skin caused by benign tumors of dermal blood
What are considered “accessory” organs of skin
Hair, nails, cutaneous glands
What are functions of hair
Vestigial
Alert us of parasites crawling on skin
Scalp retains heat/protects against sunburn
Pubic & axillary hair signify sexual maturity
Guard hairs (vibrissae): nostrils/ears
Nonverbal communication
Where is hair not found
Palms/soles/fingertips and toe tips
What are the three types of human hair
Lanugo: fine/downy/unpigmented hair appears on fetus
Vellus: fine/pale hair that replaces lanugo by time of birth
Terminal: longer, coarser, pigmented (head)
What are the 3 zones along the length of a hair
Bulb: swelling at the base where hair grow in dermis/hypodermis (start of follicle)
Root: remainder of hair follicle
Shaft: portion outside the skin
Where does mitosis occur in the hair
Hair matrix
What are the 3 layers of hair in cross section
Medulla: core of loosely arranged cells & air spaces (inner most layer)
Cortex: constitutes bulk of hair, consists of layers of elongated keratinized cells
Cuticle: consists of layers of thin scaly cells that overlap each other (outer most layer)
What structures does the hair follicle consist of
Bulb/root
Where does growth of the nail occur
Nail matrix found in nail root
What are the 5 types of glands
Merocrine sweat glands
Aprocrine sweat glands
Sebaceous glands (oil)
Ceruminous glands (earwax)
Mammary glands
Where are merocrine and apocrine sweat glands found
Merocrine: all over skin
Apocrine: groin/armpit
Which gland develops at puberty
Apocrine
Differences of basal cell and squamous cell carcinoma
basal: most common, forms in stratum basale, small shiny bump with central depression
Squamous: forms in stratum spinosum, raised/reddened/scaly appearance concave ulcer
What are the ABCD’s of malignant melanoma
Aysmmetry
Border irregularity
Color
Diameter
Which cancers metastasize rapidly
Malignant melanoma
Insensible perspiration
The amount of water we lose (500 ml/day)
Daiphoresis
Visible sweat
Bromhidrosis
Body odor produced by bacteria breaking down sweat
First degree burn
Partial thickness burn, only involve epidermis
Second degree burns
Partial thickness burn, involves epidermis & part of dermis
Debridement
Removal of eschar
