Osteology

Question 1

The study of bone:

Answer 1

osteology

Question 2

The skeletal system is composed of _______, ________, and ________ joined tightly to form a strong, flexible _______ for the body. ________, the forerunner of most bones, covers many joint surfaces in the mature skeleton.

Answer 2

bones, cartilages, ligaments, framework, Cartilage

Question 3

__________ hold bones together at the joints.

Answer 3

ligaments

Question 4

________ attach muscle to bone.

Answer 4

Tendons

Question 5

The functions of the skeleton:

Answer 5

Support, protection, movement, electrolyte balance, acid-base balance, blood formation

Question 6

Support: Bones of the lower limb, pelvis, and vertebral column ____ __ the body; nearly all bones provide support for the _______; the ______ and ______ support the teeth.

Answer 6

hold up, muscles, mandible, maxilla

Question 7

Protection: Bones enclose and protect the ______, _____ _____, ______, and ______.

Answer 7

brain, spinal cord, heart, lungs

Question 8

Movement: ______ movements, _______, and other movements are produced by the action of _____ on the bones.

Answer 8

limb, breathing, muscles

Question 9

Electrolyte balance: the skeleton stores _____ and _____ ___ and releases them into the tissue fluid and blood according to the body’s physiological needs.

Answer 9

calcium, phosphate ions

Question 10

Acid-base balance: Bone tissue buffers the blood against excessive ___ changes by absorbing or releasing alkaline salts such as calcium phosphate.

Answer 10

pH

Question 11

Blood formation: ____ bone marrow is the major producer of blood cells, including cells of the immune system.

Answer 11

Red

Question 12

Bone, or ______ _____, is a connective tissue in which the matrix is hardened by the deposition of ____ _____ and other minerals. The hardening process is called ________ or _________.

Answer 12

osseous tissue, calcium phosphate, mineralization, calcification.

Question 13

Osseous tissue is only one of the tissues that make up a bone. Also present are ____, bone marrow, cartilage, adipose tissue, ______ tissue, and fibrous connective tissue.

Answer 13

blood, nervous

Question 14

Osseous tissue continually _______ itself and interacts physiologically with all of the other organ systems of the body.

Answer 14

remodels

Question 15

Long bones: Much of it is composed of an outer shell of dense white osseous tissue called ______ (______) _______. The cylinder encloses a space called the _________ _______, or _______ ______, which contains bone marrow.

Answer 15

compact (dense) bone, medullary cavity, marrow cavity

Question 16

Long bones: At the ends of the bone, the central space is occupied by a more loosely organized form of osseous tissue called ______ (______) ______.

Answer 16

spongy (cancellous) bone

Question 17

The skeleton is about ___ compact bone and ___ spongy bone by weight. Spongy bone is found at the _____ of the long bones and in the ______ of nearly all others. It is always enclosed by more durable ______ _____.

Answer 17

3/4, 1/4, ends, middle, compact bone

Question 18

<p>
The principle features of a long bone are its shaft, called the \_\_\_\_\_\_\_, and an expanded head at each end called the \_\_\_\_\_\_\_. The \_\_\_\_\_\_ provides leverage, and the \_\_\_\_\_\_ is enlarged to strengthen the joint and provide added surface area for the attachment of tendons and ligaments.</p>

Answer 18

<p>

| diaphysis, epiphysis, diaphysis, epiphysis</p>

Question 19

Long bones: The joint surface where one bone meets another is covered with a layer of hyaline cartilage called the ____ ____. Together with a lubricating fluid secreted between the bones, this cartilage enable a joint to move ______.

Answer 19

articular cartilage, easily

Question 20

Long bones: Blood vessels penetrate into the bone through minute holes called ________ ______.

Answer 20

nutrient foramina

Question 21

Long bones: Externally, a bone is covered with a sheath called the _______. There is no _____ over the articular cartilage.

Answer 21

periosteum, periosteum

Question 22

Long bones: The internal surface of a bone is lined with _______, a thin layer of reticular connective tissue with cells that dissolve osseous tissue and others that deposit it.

Answer 22

endosteum

Question 23

In children and adolescents, an _______ _____ of hyaline cartilage separates the marrow spaces of the epiphysis and diaphysis. The ______ _____ is a zone where the bones grow in length.

Answer 23

epiphyseal plate, epiphyseal plate

Question 24

In adults, the ______ _____ is depleted and the bones can grow no longer, but an ______ ____ marks where the plate used to be. This is also know as the ________ ______.

Answer 24

epiphyseal plate, epiphyseal line, metaphysis region

Question 25

_____ _____ are conspicuously longer than wide. ____ ____ enclose and protect soft organs and provide broad surfaces for muscle attachment.

Answer 25

Long bones, Flat bones

Question 26

Boney Prominences: _______: articular surface. ______: sides of joints.

Answer 26

Condyle, Epicondyle

Question 27

Boney Prominences: ________: openings in bone/tissue. ______: narrow tube/channel.

Answer 27

Foramen, Canal

Question 28

______ ______:enhance leverage and decrease joint stress.

Answer 28

Sesamoid Bones

Question 29

Four principle types of bone cells:

Answer 29

osteogenic (osteoprogenator) cells, osteoblasts, osteocytes, osteoclasts

Question 30

_______ are bone-forming cells. They are roughly cuboidal or angular, and line up in a single layer on the bone surface under the ______ and _______ and resemble a cuboidal epithelium.

Answer 30

Osteoblasts, endosteum, periosteum

Question 31

________ synthesize the soft organic matter of the bone matrix, which then hardens by mineral deposition. Stress and fractures stimulate osteogenic cells to multiply more rapidly and quickly generate increased numbers of ______, which reinforce or rebuild the bone.

Answer 31

Osteoblasts, osteoblasts

Question 32

________ are former osteoblasts that have become trapped in the matrix they deposited. They reside in tiny cavities called _______, which are interconnected by slender channels called _______.

Answer 32

Osteocytes, lacunae, canaliculi

Question 33

_________ have multiple functions. Some resorb bone matrix and others deposit it, so they contribute to the homeostatic maintenance of both bone density and blood concentrations of calcium and phosphate ions. Perhaps even more importantly, they are _____ _____: they secrete biochemical signals that may regulate _____ _____.

Answer 33

Osteocytes, strain sensors, bone remodeling

Question 34

________ are bone-dissolving cells found on the bone surface. Bone remodeling results from the combined action of these bone-dissolving ________ and bone-depositing _______.

Answer 34

Osteoclasts, osteoclasts, osteoblasts

Question 35

The matrix of osseous tissue is, by dry weight, about ____ organic and _____ inorganic matter. The organic matter, synthesized by the _______, includes collagen and various protein-carbohydrate complexes such as glycosaminoglycans, proteoglycans, and glycoproteins.

Answer 35

1/3, 2/3, osteoblasts

Question 36

The matrix of osseous tissue: the inorganic matter is about 85% ________, a crystalized calcium phosphate salt, 10% ______ ______, and lesser amounts of magnesium, sodium, potassium, fluoride, sulfate, carbonate, and hydroxide ions.

Answer 36

hydroxyapatite, calcium carbonate

Question 37

Bone is in a class of materials that engineers call a ________ -- a combination of two basic structural materials, in this case a ceramic and a polymer. A ________ can combine the optimal mechanical properties of each component.

Answer 37

composite, composite

Question 38

In bone, the polymer is the ______ and the ceramic is the ________ and other minerals. The ceramic components enables a bone to ______ the weight of the body. The protein component gives bone a degree of ______.

Answer 38

collagen, hydroxyapatite, support, flexibility

Question 39

______ _____ forms the outer shell of all bone and also the shafts in long bones.

Answer 39

Compact bone

Question 40

The basic structural unit of ____ ____ are long cylinders around a central canal. Helices coil in one direction in one lamella and in the opposite direction in the next lamella for added _____.

Answer 40

compact bone, strength

Question 41

The skeleton receives about half a liter of blood per minute. Blood vessels, along with nerves, enter the bone tissue through _____ _____ on the surface.

Answer 41

nutrient foramina

Question 42

Along their length, central canals are joined by transverse or diagonal passages called ______ (_____) ______.

Answer 42

perforating (Volkmann) canals

Question 43

The inner and outer boundaries of dense bone are arranged in ________ _____ that run parallel to the bone surface. Between osteons, we can find irregular regions called _____ ______, the remains of old osteons that broke down as the bone grew and remodeled itself.

Answer 43

circumferential lamellae, interstitial lamellae

Question 44

Spongy bone consists of a lattice of delicate slivers of bone called ______ (rods or spines) and ______ (thin plates).

Answer 44

spicules, trabeculae

Question 45

Although calcified and hard, ____ ____ is named for its spongelike appearance. It is permeated by spaces filled with _____ ______.

Answer 45

spongy bone, bone marrow

Question 46

The matrix of spongy bone is arranged in lamellae like those of compact bone, but there are few ______. _____ _____ are not needed here because no osteocyte is very far from the marrow.

Answer 46

osteons, Central canals

Question 47

Spongy bone is well designed to impart ______ to a bone while adding a minimum of ______. Its trabeculae are not randomly arranged as they might seem at a glance, but develop along the bone's lines of _____.

Answer 47

strength, weight, stress

Question 48

_______ _______ is a general term for soft tissue that occupies the marrow cavity of a long bone, the spaces amid the trabeculae of spongy bone, and the larger central canals.

Answer 48

Bone marrow

Question 49

In a child, the marrow cavity of nearly every bone is filled with ____ _____ _____ (______ ____). This is often described as _____ _____ -- tissue that produces blood cells -- but it is actually composed of multiple tissues in a delicate but intricate arrangement, and is properly considered an organ unto itself.

Answer 49

red bone marrow (myeloid tissue), hemopoietic tissue

Question 50

In adults, most of the red marrow turns to fatty _____ _____ ______, which no longer produces _____.

Answer 50

yellow bone marrow, blood

Question 51

In adults, ____ ____ is limited to the skull, vertebrae, ribs, sternum, part of the pelvic (hip) girdle, and the proximal heads of the humerus and femur.

Answer 51

red marrow

Question 52

The formation of bone is called _______ or ______. In the human fetus and infant, bone develops by two methods called ______ and ______ ______.

Answer 52

ossification, osteogenesis, intramembranous, endochondral ossification.

Question 53

______ _______: embryonic connective tissue up to the 6th week of fetal development. Fetal cartilage template of skeleton made of _____ _____.

Answer 53

Intramembranous Ossification, fibrous membranes

Question 54

_______ ______ is a process in which a bone develops from a preexisting model composed of hyaline cartilage.

Answer 54

Endochondral Ossification

Question 55

_______ ______ begins around the sixth week of fetal development and continues into a person's 20s.

Answer 55

Endochondral Ossification

Question 56

Most bones of the body, including the vertebrae, ribs, sternum, scapula, pelvis, and bones of this limbs, develop this way.

Answer 56

Endochondral Ossification

Question 57

Endochondral Ossification: Blood vessels penetrate the bony collar and invade the primary ossification center. As the center of the model is hollowed out and filled with blood and stem cells, it becomes the _____ _____ _____.

Answer 57

primary marrow cavity

Question 58

Primary Ossification Center: In the primary marrow cavity, various stem cells introduced with the blood give rise to ____ and ____. ____ line the cavity, begin depositing osteoid tissue, and calcify it to form a temporary network of bony _______.

Answer 58

osteoblasts, osteoclasts, Osteoblasts, trabeculae

Question 59

Primary Ossification Center: As the bony collar under the periosteum thickens and elongates, a wave of cartilage death progresses toward the _____ of the bones. ______ in the marrow cavity follow this wave, dissolving calcified cartilage remnants and enlarging the marrow cavity of the diaphysis.

Answer 59

ends, Osteoclasts

Question 60

Primary Ossification Center: The region of transition from cartilage to bone at each end of the primary marrow cavity is called a ______.

Answer 60

metaphysis

Question 61

Primary Ossification Center: Chondrocyte enlargement and death occur in the epiphysis of the model as well, creating a _______ _______ ______.

Answer 61

secondary ossification center

Question 62

The secondary ossification center becomes hollowed out by the same process as the diaphysis, generating a _____ _____ _____ in the epiphysis. This cavity expands _____ from the center, in ___ directions.

Answer 62

secondary marrow cavity, outward, all

Question 63

During infancy and childhood, the ______ fill with spongy bone. Cartilage is then limited to the articular cartilage covering each joint surface, and to an _________ _____, a thin wall of cartilage separating the primary and secondary marrow cavities at one or both ends of the bone. The ____ ____ persists through childhood and adolescence and serves as a growth zone for bone elongation.

Answer 63

epiphyses, epiphyseal plate, epiphyseal plate

Question 64

By the late teens to early twenties, all remaining cartilage in the ______ ____ is generally consumed and the gap between the ______ and _____ closes. The ____ and ____ marrow cavities then unite into a single cavity, and the bone can no longer grow in length.

Answer 64

epiphyseal plate, epiphysis, diaphysis, primary, secondary

Question 65

_______ does not end at birth, but continues throughout life with the growth and remodeling of bones. Bones grow in two directions: _____ and ____.

Answer 65

Ossification, length, width

Question 66

The _______ ______ is a region of transition from cartilage to bone, and functions as a growth zone where the bones elongate.

Answer 66

epiphyseal plate

Question 67

The epiphyseal plate consists of typical ____ cartilage in the middle, with a transitional zone on each side where cartilage is being replaced by bone. The transitional zone, facing the marrow cavity, is called the ______.

Answer 67

hyaline, metaphysis

Question 68

Bone elongation is really a result of cartilage growth. Cartilage growth from within, by the multiplication of chondrocytes and deposition of new matrix in the interior, is called _____ _____.

Answer 68

interstitial growth

Question 69

Bones also continually grow throughout life in diameter and thickness. This involves a process called _____ _____, the deposition of new tissue at the surface.

Answer 69

appositional growth

Question 70

In addition to their growth, bones are continually ______ throughout life by the absorption of old bone and deposition of new. The process replaces about ___ of the skeletal tissue per year. It repairs microfractures, releases minerals into the blood, and reshapes bones in response to use and disuse.

Answer 70

remodeled, 10%

Question 71

____ ____ of ____ states that the architecture of a bone is determined by the mechanical stresses placed upon it, and the bone thereby adapts to withstand those stresses.

Answer 71

Wolff's law of bone

Question 72

Bone remodeling comes about through the collaborative action of ______ and _____.

Answer 72

osteoblasts, osteoclasts

Question 73

The most common bone disease is ______, a severe loss of bone density.

Answer 73

osteoporosis

Question 74

Osteoporosis affects especially ____ ___, since this is more metabolically active than dense bone and has more surface area exposed to bone-dissolving osteoclasts.

Answer 74

spongy bone

Question 75

In osteoporosis, the bones become _____ and highly subject to pathologic ____ from stresses as slight as sitting down too quickly. Fractures occur especially in the ____, ____, and ____ ___.

Answer 75

brittle, fractures, hip, wrists, vertebral column

Question 76

In osteoporosis, as the vertebrae lose bone, they become compressed and the spine is often deformed into a condition called ____ ("_____ ____").

Answer 76

kyphosis, widow's hump

Question 77

In osteoporosis, complications of the resulting loss of mobility are ______ and _____.

Answer 77

pneumonia, thrombosis

Question 78

What types of people are at the greatest risk of osteoporosis?

Answer 78

postmenopausal white women

Question 79

White women begin loosing bone density as early as age _____. By age 70, the average white woman looses ____ of her bone tissue.

Answer 79

35, 30%

Question 80

Other than age, race, and sex, some other risk factors for osteoporosis include ______, ______ _____, ___ ____, and inadequate ____ ____ ____.

Answer 80

smoking, diabetes mellitus, poor diet, weight-bearing excercise

Question 81

Osteoporosis: Until menopause, _____ maintains bone density by inhibiting ______.

Answer 81

estrogen, osteoclasts

Question 82

Osteoporosis is common in young female athletes. The percentage of body fat is so low that they stop _____ and ovarian _____ _____ is low.

Answer 82

ovulating, estrogen secretion

Question 83

Treatments for osteoporosis are aimed at slowing the rate of _____ _____. ______ replacement therapy is out of favor because it increases the risk of breast cancer, stroke, and coronary artery disease. The bisphosphonates (Fosamax, Actonel), among the current preferred treatments, act by destroying _______.

Answer 83

bone resorption, Estrogen, osteoclasts

Question 84

The best treatment for osteoporosis is ______. Exercise and _____ and _____ intake are good bone building tools.

Answer 84

prevention, calcium, vitamin D

Question 85

Osteoporosis drug side effects include:

Answer 85

osteonecrosis of the jaw, atypical fractures of the femur, gastric ulcers, and thick brittle bones.