A&P CHAPTER 6 STUDY NOTES

Bone tissue and the skeletal system perform several basic functions.

-They provide support of soft tissues and attachment sites for muscles, creating a framework for the body. -Protection from injury is afforded to internal organs by bones which overlie and/or surround them.-Movement is facilitated since bones provide leverage for muscle contraction.-Mineral homeostasis, particularly of calcium and phosphorus, occurs as minerals are stored in bones and can be mobilized when needed elsewhere in the body.-Blood cell production occurs in the red bone marrow formed in certain bones. -Storage of energy occurs in the lipids found in yellow bone marrow.

Bone tissue and the skeletal system

1. They provide support of soft tissues and attachment sites for muscles, creating a framework for the body. 2. Protection from injury is afforded to internal organs by bones which overlie and/or surround them. 3. Movement is facilitated since bones provide leverage for muscle contraction. 4. Mineral homeostasis, particularly of calcium and phosphorus, occurs as minerals are stored in bones and can be mobilized when needed elsewhere in the body. 5. Blood cell production occurs in the red bone marrow formed in certain bones. 6. Storage of energy occurs in the lipids found in yellow bone marrow.

fracture

A _______ is any break in bone

parathyroid hormone (PTH)

An important hormone regulating Ca2+ exchange between bone and blood is _______, secreted by the parathyroid glands; it increases blood Ca2+ level.

mesenchymal cells

An ossification center forms from ________ as they convert to osteoblasts and lay down osteoid matrix.

calcitonin (CT)

Another hormone that contributes to the homeostasis of blood Ca2+ is _______; it is secreted by the thyroid gland and decreases blood Ca2+ level.

limb buds

Around the fifth week of embryonic life, extremities develop from _____, which consist of mesoderm and ectoderm

interstitial growth.

Because of the activity of the epiphyseal plate, the diaphysis of a bone increases in length by ____________

interstitial growth

Because of the activity of the epiphyseal plate, the diaphysis of a bone increases in length by.

ossification (osteogenesis)

Bone forms by a process called ________, which begins when mesenchymal cells become transformed into osteoprogenitor cells, which undergo cell division, giving rise to cells that differentiate into osteoblasts and osteoclasts.

intramembranous or endochondral

Bone forms from mesoderm by ______ossification.

interstitial and appositional addition

Bone grows in diameter as a result of ________ of new bone tissue by osteoblasts around the outer surface of the bone and to a lesser extent internal bone dissolution by osteoclasts in the bone cavity.

interstitial and appositional addition

Bone grows in diameter as a result of __________ of new bone tissue by osteoblasts around the outer surface of the bone and to a lesser extent internal bone dissolution by osteoclasts in the bone cavity.

hand plates and foot plates

By the sixth week, a constriction around the middle portion of the limb buds produces___________, which will become hands and feet.

Ca2+

Calcium

diaphysis

Compact bone lies over spongy bone and composes most of the bone tissue of the _____.

fracture hematoma

Fracture repair involves formation of a clot called a__________

protects, supports, and resists stress

Functionally, compact bone......

stores red marrow and provides some support.

Functionally, spongy bone.....

hardness and tensile strength

Mineral salts confer ____ on bone while collagen fibers give bone its great _____.

osteoporosis

Of two principal effects of aging on bone, the first is the loss of calcium and other minerals from bone matrix (demineralization), which may result in _______

osteoclasts

Old bone is constantly destroyed by ______, whereas new bone is constructed by osteoblasts.

diaphysis (shaft), epiphyses (ends), metaphysis, articular cartilage, periosteum, medullary (marrow) cavity, and endosteum

Parts of a typical long bone are the

demineralization (loss of bone minerals)

Removal of mechanical stress weakens bone through ___________ and collagen reduction.

short, flat, and irregular bones, and the epiphyses of long bones.

Spongy bone forms most of the structure of

cartilage, bone, bone marrow, and the periosteum.

Structurally the skeletal system contains four types of connective tissue

cartilage, bone, bone marrow, and the periosteum

Structurally the skeletal system contains four types of connective tissue:

nutrient artery

The _______ passes through the nutrient canal and sends branches into the central Haversian canals to provide for osteocytes.

primary ossification center

The _________ of a long bone is in the diaphysis.

periosteal arteries

The __________ pass through Volkman's canals to a multitude of vessels that supply the outer compact bone region

medullae

The artery continues into the _____ to supply blood for the marrow and osteocells via the epiphyseal artery.

medullae

The artery continues into the _______ to supply blood for the marrow and osteocells via the epiphyseal artery.

the zone of resting cartilage, the zone of proliferating cartilage, the zone of hypertrophic cartilage, and the zone of calcified cartilage.

The epiphyseal plate consists of four zones:

zone of resting cartilage zone of proliferating cartilage zone of hypertrophic cartilage and zone of calcified cartilage.

The epiphyseal plate consists of four zones:

osteoprogenitor cells, osteoblasts, osteocytes, and osteoclasts.

The four principal types of cells in bone tissue are

hydroxyapatite

The matrix of bone contains abundant mineral salts, primarily ____ and some calcium carbonate.

hydroxyapatite

The matrix of bone contains abundant mineral salts, primarily __________ and some calcium carbonate.

partial, complete, closed (simple), open (compound), comminuted, greenstick, spiral, transverse, impacted, displaced, nondisplaced, stress, pathologic, Pott's, and Colles'

The types of fractures include:

epiphyseal plate.

To understand how a bone grows in length, one needs to know some of the details of the structure of the

epiphyseal plate.

To understand how a bone grows in length, one needs to know some of the details of the structure of the _________.

____ help build and retain bone mass.

Weight-bearing activities, such as walking or moderate weightlifting

increasing deposition

Within limits, bone has the ability to alter its strength in response to mechanical stress by _______ of mineral salts and production of collagen fibers.

Bone (osseus) tissue forms

_____ most of the skeleton, the framework that supports and protects our organs and allows us to move.

The periosteum

_____-first forms a collar of spongy bone that is then replaced by compact bone.

Nerves

______ follow vessels into bone tissue and the periosteum where they sense damage and transmit pain messages.

Bone (osseus) tissue

______ forms most of the skeleton, the framework that supports and protects our organs and allows us to move.

Osteoblasts

______ lay down bone.

Vessels

_______ are needed to supply the various bone tissues with both nutrients and waste disposal through a number of interconnective canals in the bone matrix.

Spongy (cancellous) bone

________ does not contain osteons. It consists of trabeculae surrounding many red marrow-filled spaces.

Remodeling

________ is the ongoing replacement of old bone tissue by new bone tissue.

Intramembranous ossification

________ occurs within fibrous membranes of the embryo and the adult.

Endochondral (intracartilaginous) ossification

________ refers to the formation of bone with a hyaline cartilage model.

Compact (dense) bone tissue; osteons (Haversian systems)

_________ consists of _______ with little spaces between them.

Secondary ossification centers

____________ develop in the epiphyses, where bone replaces cartilage, except for the epiphyseal plate.

Bone (osseus) tissue

_______consists of widely separated cells surrounded by large amounts of matrix.

Osteoporosis

______is a decrease in the amount and strength of bone tissue owing to decreases in hormone output. In osteoporosis, bone resorption outpaces bone formation.

A fracture

______is any break in bone.

The calcifying matrix centers

______join to form bridges of trabeculae that constitute spongy bone with red marrow between.

Intramembranous ossification

______occurs within fibrous membranes of the embryo and the adult.

The periosteal arteries

______pass through Volkman's canals to a multitude of vessels that supply the outer compact bone region.

Endochondral (intracartilaginous) ossification

______refers to the formation of bone with a hyaline cartilage model.

The notochord

_____is a flexible rod of tissue that lies in a position where the future vertebral column will develop.

Paget's disease

_____is characterized by massive osteoclastic resorption and extensive bone formation.

The primary ossification center

_____of a long bone is in the diaphysis.

The nutrient artery

_____passes through the nutrient canal and sends branches into the central Haversian canals to provide for osteocytes.

Vessels

are needed to supply the various bone tissues with both nutrients and waste disposal through a number of interconnective canals in the bone matrix.

Compact (dense) bone tissue

consists of osteons (Haversian systems) with little spaces between them.

Bone (osseus) tissue

consists of widely separated cells surrounded by large amounts of matrix.

bony (hard) callus

conversion of the fibrocartilaginous callus into the spongy bone of a ____________, and, finally, remodeling of the callus to nearly original form.

Secondary ossification centers

develop in the epiphyses, where bone replaces cartilage, except for the epiphyseal plate.

Spongy (cancellous) bone

does not contain osteons. It consists of trabeculae surrounding many red marrow-filled spaces.

Nerves

follow vessels into bone tissue and the periosteum where they sense damage and transmit pain messages.

calcification, or mineralization.

hydroxyapatite and a few other salts are deposited in a framework of collagen fibers, a process called

calcification, or mineralization.

hydroxyapatite and a few other salts are deposited in a framework of collagen fibers, a process called ___________

Remodeling

is the ongoing replacement of old bone tissue by new bone tissue.

Cartilage degenerates

leaving cavities that merge to form the medullary cavity.

procallus

organization of the fracture hematoma into granulation tissue called ________.

types of fractures

partial, complete, closed (simple), open (compound), comminuted, greenstick, spiral, transverse, impacted, displaced, nondisplaced, stress, pathologic, Pott's, and Colles'.