Chapter Six – Skeletal System

A comprehensive set of flashcards capturing key concepts, facts, and definitions from the lecture on the skeletal system.

What is mindset as defined in the lecture?

The driving force in the quest for success and achievement, combining discipline, strength, confidence, and ambition.

How many major bones are there in the human skeleton?

206 major bones.

What are the two parts of the skeletal system?

The appendicular (appendages) and the axial (bones of the midline of the body).

What are the primary functions of the skeletal system?

Structural support, storage of minerals, blood cell production, protection of underlying organs, and leverage to keep the body upright.

What are the six classifications of bones by shape?

Sutural bones, short bones, flat bones, long bones, sesamoid bones, and irregular bones.

What type of bone is primarily composed of spongy bone and surrounded by compact bone?

Epiphysis.

What is ossification?

The process of bone formation, which includes endochondral ossification and intramembranous ossification.

What are the roles of osteoblasts and osteoclasts in bone homeostasis?

Osteoblasts build bone, while osteoclasts recycle bone.

What mineral is most abundant in the body and vital for the skeletal system?

Calcium.

What is osteoporosis?

A condition characterized by severe bone loss and affects normal function, typically occurring in individuals over the age of 45.

What is the role of calcitonin in calcium regulation?

Calcitonin decreases calcium ion levels by inhibiting osteoclast activity and increasing calcium excretion at kidneys.

What are the four steps in the repair of fractures?

1. Formation of a blood clot. 2. Formation of a callus by cells of the endosteum and periosteum. 3. Osteoblasts repair the ends of the bone. 4. Remodeling of the fracture by osteoblasts and osteocytes.

What are the effects of aging on the skeletal system?

Bones become thinner and weaker, leading to conditions like osteopenia and osteoporosis.

What is osteosarcoma?

The most common malignancy of bone in adolescents, characterized by bone pain and may present as a 'sun burst' appearance on radiography.

What distinguishes endochondral ossification from intramembranous ossification?

Endochondral ossification ossifies bones that originate as hyaline cartilage, while intramembranous ossification occurs in the dermis and produces dermal bones.

What factors influence bone growth and maintenance?

Exercise, nutrition, and hormonal factors.

What is the function of the periosteum?

Isolates bone from surrounding tissues, provides a route for circulatory supply, and participates in bone growth and repair.

How does vitamin D3 affect the skeletal system?

It is necessary for the synthesis of calcitriol, which helps absorb calcium and phosphorus from the digestive tract.

Bone Cells make up what percentage of bone mass?

2%

Storage of Minerals of Ca+

salts, which is the most abundant mineral of the body. The way body regulates blood serum Ca+ levels.

Blood cell production

makes RBC’s and WBC’s in the bone marrow of long bones

protection of underlying organs

Hard bones around the brain, thoracic cavity and reproductive organs

leverage to keep the body upright

The heaviest bones are centrally located to keep the organism, centrally balanced

bones are classified by

Shape

Internal tissue

Bone markings

sutural bones

small irregular bones found between flat bones of the skull.

short bones

These are boxy shaped examples of these are ankle, ankles, and wrist bones

flat bones

Thin, broad bones found in the skull sternum ribs and scapula. These allow for muscle attachments and greater surface area.

parietal bones of skull

bone tissue - osseous

dense, supportive, connective tissue

Contain specialized cells

Produces solid matrix of calcium salt deposits

Long bones

Appendages

• long & thin

• phalanges, humorous, femur, tibia/fibula, radius/ulna

sesamoid bones

small flat bones

develop inside tendons near joints of knees, hands, and feet

irregular bones

Irregular bones have complex shades with short flats, notched, or rigid surface

bone markings

Depressions or grooves along bone surf

Elevations or projections

Tunnels were blood and nerves and her bone

Metaphysis

The middle aspect at each end of the bone.

Diaphysis

the shaft

I have a wall of compact bone or dense bone.

Has A central medullary cavity

osteocytes

Mature bone cells forming a pathway to exchange nutrients and waste

containing calcium salts

periosteum

covers outer surfaces of bones

Osteocytes

mature bone cells that maintain the bone matrix

Lives in the lacunae

are between layers lamellae of matrix

2 major functions of osteocytes

1. maintain protein and mineral

2. help repair damaged bone

osteoblasts

build bone .

osteoid

osteoblast without calcium

Osteoblast surrounded by the bone then they become osteocytes

osteoclasts

Breakdown bone

osteogenesis cells

mesenchymal stem cells - divide to produce osteoblasts

osteolysis

process to break down bone

homeostasis

Bone building and bone recycling must balance

osteon

basic unit , 1 unit.

osteocytes

arranged in concentric lamellae

perforating canals

perpendicular to the central canal

weight bearing bones

from femur to tibia

transfer weight to hip joint then to knee

transfers kinetic energy forces to compact cone on the medial aspect to support body upright

periosteum

outer layer of bones.

covers all bones except parts enclosed in joint

functions of periosteum

1. Isolate bone from surrounding tissues.

Endosteum

inner lining of the bone where the medullary cavity is.

appositional growth

100lbs puberty hits for girls . compact bone thickens and strengthens long bone .

epiphyseal line

long bones stop growing after puberty.

epiphyseal cartilage disappears

mature bones

osteoclasts enlarge medullary

process of remodeling

bone continually remodels, recycles and replaces..

vitamin C

required for collagen synthesis and stimulation of osteoblast differentiation

vitamin A

Stimulates osteoblast activity

Vitamin K

help synthesize bone proteins

The skeleton as a calcium reserve

Bone store, calcium, and other minerals

Calcium is the most abundant mineral in the body

how much calcium in bone

39%

how much potassium in bone

0.2%

how much sodium in bone

0.7%

how much magnesium in bone

0.5%

how much carbonate in bone

9.8%

how much phosphate in bone

17%

total organic components

67%

organic compounds in bone

33%

bone contains 99% of the bodies?

Calcium

bone contains 4% of the bodies?

Potassium

bone contains 35% of the bodies?

sodium

bones contain 50% of the bodies?

Magnesium

bone contains 80% of the bodies

Carbonate

bone contains 99% of the bodies

Phosphate

fractures

cracks or breaks in bones

caused by physical stress

compression fractures

jumping from high height

epiphyseal fractures

happens in a child before puberty

green stick feacture

tiny nic in the bone, usually younger or older

colle’s fractures

happens in elderly people usually on radius bone

potts fractures

soccer players, ankles bones.

osteopenia

when bone becomes demineralized between ages 30 & 40

Osteoporosis - loss of spongy bone mass

over age of 50

• 29% of women

• 18% of men

osteosarcoma

the most common malignancy of bone seen in an adolescent child.

60-70% of patients survive 5 yrs or more

osteoma

benign tumor in children and adolescents. remove with laser