Chapter 7 Skeletal System: Bone Structure & Function

List the structures of the skeletal system

Compare and contrast compact and spongy bone.

Identify the types and locations of cartilage within skeletal system.

1. hyaline cartilage - location(s): rib to sternum, end of bones, within growth plates

2. fibrocartilage - location(s): invertebral discs, pubic symphysis, cartilage pads of knees

In what three locations of the body do you find fibrocartilage?

intervertebral discs

pubic symphysis

cartilage pads of knees

Compare and contrast spongy bone and compact bone.

spongy bone is deeper than compact bone, appears porous, 20% bone mass

compact bone is dense bone and connective tissue, white, smooth, solid, 80% bone mass

Describe the general functions of bone.

Describe the four major classes of bones as determined by shape.

Explain the structural components of a long bone.

Compare the gross anatomy of other bones to that of a long bone.

Explain the general function of blood vessels and nerves that serve a bone.

Compare and contrast the structure and location of the two types of bone marrow.

Name the four types of bone cells and their functions.

Describe the composition of bone's matrix.

Explain bone matrix formation and resorption.

Compare the structure of compact bone and spongy bone.

Analyze the structure of hyaline cartilage and the cells in its matrix.

Calcium is one of the minerals stored and released from the bone. What are some of its functions within the body?

muscle contraction

blood clotting

nerve impulse transmission

What type of bones have a length nearly equal to their width?

short bones

What portion of bone contains the epiphyseal plate?

long bone

metaphysis

Where is red bone marrow found in the adult skeleton?

skull

vertebrae

ribs

sternum

ossa coxae

proximal epiphyses of humerus/femur

What is the process of blood cell formation called?

hemopoiesis

Describe the gross anatomy of a long bone.

bigger in length than width

elongated, cylandrical shape

most common shape

upper/lower limbs

Name several functions of bone.

support

protection

movement

blood cell production

storage of minerals/energy reserves

What is the function of an osteoblast?

involved in bone formation, form bone tissue

What is the function of an osteoclast?

involved in bone reabsorption

What organic substances compose bone matrix?

osteoid composed of:

collagen, proteoglycans, and glycoproteins.

What inorganic substances compose bone matrix?

formed from hydroxyapatite, which includes:

salt crystals and calcium phosphate. Other salts and ions such as calcium carbonate, sodium, magnesium, sulfate, flouride

What cells secrete cartilage matrix?

chondroblasts

What cells maintain cartilage matrix?

chondrocytes

Identify bones that are produced by intramembranous ossification.

Explain the four main steps in intramembranous ossification.

Explain the steps in endochondral ossification of a long bone.

Differentiate between intramembranous ossification and endochondral ossification.

What bones are formed from intramembranous ossification?

flat bones of skull

some facial bones

mandible

central part of clavicle

In what portion of a long bone do primary ossification centers form?

diaphysis

Where are secondary ossification centers?

epiphysis

Compare and contrast the five zones of the epiphyseal plate, and describe how growth in length occurs there.

Describe the steps of appositional growth.

Define bone remodeling, and give examples of how it varies in different bones and different portions of the same bone.

Explain the effect of mechanical stress on bone remodeling.

occurs in weight bearing movement, needed for bone remodeling, increase bone strength, increase bone mass when exercise but decrease bone mass when no mechanical stress happening

Identify the hormones that influence bone growth and bone remodeling, and describe their effects.

growth hormones - somatotropin, stimulate liver to produce somatomedin, both directly stimulate growth of cartilage in epiphyseal plate

thyroid hormone - secrete by thyroid gland, affect BMR of bone cells, regulate normal activity at epiphyseal plate

sex hormones - estrogen and testosterone accelerate bone growth in puberty, ?

glucocorticoids - steroid hormones regulate blood glucose but high amounts can increase bone loss

serotonin - also a neurotransmitter, role of rate and regulation of bone remodeling but if levels too high osteoprogenitor cells affected and bone density disorders

What is the term for bone growth in width?

appositional growth

What is the term for bone growth in length?

interstitial growth

What hormone stimulates the liver to produce somatomedin, causing cartilage proliferation at the epiphyseal plate?

somatomedin

Explain the activation of vitamin D to calcitriol.

Discuss the release of parathyroid hormone.

Explain how parathyroid hormone and calcitriol function together to regulate blood calcium levels.

Discuss homeostatic system involving the hormone calcitonin and its effect on blood calcium levels.

What organs are involved in activating vitamin D3 to calcitriol?

small intestines

liver

kidney

parathyroid gland

Parathyroid hormone and calcitriol are secreted in response to what?

How does calcitonin work on bone CT and kidneys to regulate blood calcium levels?

Describe how aging influences bone structure.

What condition displays a reduction in bone mass by loss of calcium and or minerals, but without yet compromising normal function?

Characterize decreased tensile strength of bone due to aging?

Characterize decreased tensile strength of bone due to aging?

Explain the four steps by which fractures heal.

What are four basic steps in fracture repair?