Mastering A&P Chapter 6 - Bones and Skeletal Tissues

Which bone-forming process is shown in the figure? (Third picture) intramembranous ossification bone remodeling endochondral ossification bone fracture repair

Endochondral ossification The figure illustrates a step in the embryonic formation of a bone from a cartilage model.

Osteoid-producing osteoblasts must rely upon this organelle to produce primary structures leading to the formation of collagen and calcium-binding proteins. peroxisomes ribosomes centrioles mitochondria

Ribosomes

Which of the following pairs is MISMATCHED? sternum: long bone skull bones: flat bones tarsals: short bones femur: long bone

Sternum: long bone The sternum is a flat bone.

The arrow in the figure is pointing to which of the following structures? the epiphyseal plate a secondary ossification center a primary ossification center the articular cartilage

The epiphyseal plate During endochondral ossification, a distinct epiphyseal plate is formed at the boundary between primary and secondary ossification centers.

The structural unit of compact bone (osteon) resembles the growth rings of a tree trunk. True or False

True

Which structure is seen at the arrow? diaphysis periosteal bud epiphyseal plate bone collar

Bone collar A collar of ossified tissue forms around the bone in the early stages of ossification.

For intramembranous ossification to take place, which of the following is necessary? A) A bone collar forms around the cartilage model. B) An ossification center forms in the fibrous connective tissue. C) The cartilage matrix begins to deteriorate. D) A medullary cavity forms.

B) An ossification center forms in the fibrous connective tissue.

The cell responsible for secreting the matrix of bone is the ________. A) osteocyte B) osteoblast C) osteoclast D) chondrocyte

B) osteoblast

During bone growth, which event is most significant at the surface indicated by the letter B? Ossification of the epiphysis of a long bone. cell division of chondrocytes conversion of bone into cartilage calcification of the cartilage matrix formation of compact bone

Calcification of the cartilage matrix Calcification of the cartilage matrix leads to its deterioration and replacement by bone.

Bones are classified by whether they are weight bearing or protective in function. True or False

False

The periosteum is a tissue that serves only to protect the bone because it is not supplied with nerves or blood vessels. True or False

False

Yellow bone marrow contains a large percentage of ________. A) fat B) blood-forming cells C) elastic tissue D) Sharpeyʹs fibers

Fat

Which of the following would NOT be a way that parathyroid hormone (PTH) could alter plasma calcium levels? (Which one of the following is FALSE?) increase osteoclasts increase reabsorption of calcium in the kidney increase osteoblasts on bone

Increase osteoblasts on bone Correct. This answer is false. PTH would NOT increase osteoblasts. Osteoblasts store calcium on bone, thus lowering plasma calcium levels.

central (Haversian) canal A central (or Haversian) canal runs lengthwise at the center of each osteon.

The blood vessels and nerve in the figure are found within which type of space? perforating (Volkmann's) canal marrow cavity central (Haversian) canal canaliculi

Osteocytes, literally "bone cells," are the primary structural and maintenance cells found in bone.

What type of cell is shown at A? osteoblast osteoclast osteocyte mesenchyma

adipose tissue Yellow bone marrow within the medullary cavity is composed primarily of adipose tissue (fat).

Which of the following is the major component of the part of the bone labeled E? hyaline cartilage adipose tissue osseous tissue dense connective tissue

Remodeling a kitchen to add additional cabinets to existing ones also means adding extra support. In a similar respect, bone remodeling alters bone structure without adversely affecting bone strength. What divalent cation is required to create additional bone matrix support? calcium phosphate carbonate chloride

calcium

Mechanical stress on weight-bearing bones plays a large part in bone remodeling. What single factor plays the largest role in maintaining adequate bone strength? cartilage vitamin E gravity bone length

gravity

an osteon The circular structural unit found within compact bone is termed the osteon, and consists of a central canal surrounded by layers of bone.

The structures in the figure collectively form which structural unit of bone? trabeculae an osteon central canal diploë

An osteon contains osteocytes, lamellae, and a central canal, and is found in compact bone only. True or False

True

A fracture in the shaft of a bone would be a break in the ________. a) epiphysis b) metaphysis c) diaphysis d) articular cartilage

c) diaphysis dia = through physis = growth diaphysis or shaft forms the long axis of the bone.

Bones are covered and lined by a protective tissue called periosteum. The inner (osteogenic) layer consists primarily of ________. a) cartilage and compact bone b) marrow and osteons c) osteoblasts and osteoclasts d) chondrocytes and osteocytes

c) osteoblasts and osteoclasts bone-germainators and bone breakers.

Osteoblasts __________. maintain bone matrix break down bone form skeletal cartilage

form new bone Osteoblasts are the bone-forming cells that produce new bone.

What is intramembranous ossification? the formation of bone from fibrous membranes the formation of bone from preexisting elastic cartilage models the formation of bone from preexisting hyaline cartilage models the formation of bone from preexisting fibrocartilage models

he formation of bone from fibrous membranes The formation of bone from fibrous membranes is called intramembranous ossification.

Classify the cells seen at the arrow in A. chondroblasts osteocytes osteoclasts osteoblasts

osteoblasts Osteoblasts ("bone makers") begin bone formation by secreting the bone matrix.

Which of the following best describes the process shown in the figure? the formation of bone in a preexisting cartilage model bone repair at a site of fracture the formation of bone in a membrane bone remodeling in response to changes in mechanical stress

the formation of bone in a membrane The figure illustrates the formation of new bones within a fibrous membrane ("intramembranous") during embryonic development.

In which of the labeled parts of the adult long bone would hematopoietic tissue be located? Primary features of a long bone. A B C D E

B Hematopoietic tissue is found in the spaces within the red bone marrow found within certain body locations consisting of spongy bone. Examples include the diploe of flat bones and the proximal epiphyses of the femur and humerus (pictured).

During bone growth, which significant event occurs at the surface indicated by the letter D? Ossification of the epiphysis of a long bone. production of hyaline cartilage bone resorption interstitial growth production of compact bone

Bone resorption As the bone widens, the matrix at the endosteal surface is resorbed to maintain the proper thickness of the walls surrounding the medullary cavity.

Which of the following hormones is currently thought to decrease plasma calcium levels in pregnant women and children? parathyroid hormone (PTH) calcitonin calcitriol thyroid hormones

Calcitonin Yes, calcitonin is currently thought to decrease plasma calcium levels in children and pregnant women.

Which hormone works directly in the intestine to increase plasma calcium levels? calcitriol parathyroid hormone (PTH) calcitonin

Calcitriol Yes, parathyroid hormone (PTH) activates Vitamin D into calcitriol in the kidney. Calcitriol then increases absorption of calcium in the intestine.

PTH promotes the formation of which hormone? vitamin D calcitriol thyroid hormones calcitonin

Calcitriol Yes, parathyroid hormone promotes the formation of calcitriol.

Which of the following statements is true? Endochondral ossification leads to the formation of the clavicles and cranial bones. Most bones in the body are formed by intramembranous ossification. Endochondral ossification converts hyaline cartilage "bone" models into true bones (i.e., hyaline cartilage serves as a template for bone formation). Endochondral ossification occurs within fibrous connective tissue membranes.

Endochondral ossification converts hyaline cartilage "bone" models into true bones (i.e., hyaline cartilage serves as a template for bone formation). Endochondral ossification is the formation of bone within hyaline cartilage. Hyaline cartilage "bones" are used as templates for the formation of true bone. Most bones below the base of the skull form by endochondral ossification.

Bones do NOT have a role in __________. support glycogen production movement fat storage blood cell formation

Glycogen production Glycogen production (glycogenesis) is not a role of bone; it takes place primarily in muscle and liver cells.

What material makes up most of the structure at A? hyaline cartilage dense irregular connective tissue elastic cartilage fibrocartilage

Hyaline cartilage The articular cartilage at the ends of long bones is formed from hyaline cartilage.

The structure indicated by the arrow is composed primarily of what tissue? Late stage in ossification of a long bone. hyaline cartilage mesenchyme fibrocartilage dense connective tissue

Hyaline cartilage The cartilage models used to form bones are composed of hyaline cartilage. This tissue persists within the epiphyseal plate at the boundary between primary and secondary ossification centers until early adulthood.

There are several components to a functional osteon. Changes to which of the following components would make the bones less strong overall and cause the bones to bend under a person's body weight? hydroxyapatite periosteum osteoid articular cartilage

Hydroxyapatite The hydroxyapatite is the rigid portion of the bone matrix. As hydroxyapatite is removed from the bone, more of the body's weight would be transferred to the collagen of the osteoid, which would bend under the weight.

What is the term for the layers of bony matrix surrounding the cell at A? periosteum lamellae endosteum lacunae

Lamellae Lamellae are layers of bony matrix synthesized by osteoblasts during bone growth and maintenance.

An imbalance that activates these bone cells would lead to a loss of bone density. osteoblasts chondroblasts osteocytes osteoclasts

Osteoclasts are the bone cells that break down bone. If they were activated more than normal, you should expect to see bone loss.

Which description of bone cells is INCORRECT? Osteoblasts secrete collagen and calcium-binding proteins. Osteogenic cells can differentiate into osteoclasts. Osteoclasts secrete digestive enzymes and hydrogen ions. Bone lining cells on the internal surfaces of bone are also called endosteal cells.

Osteogenic cells can differentiate into osteoclasts Osteoclasts are derived from the same hematopoietic stem cells that differentiate into macrophages; they are not derived from osteogenic cells.

What is the structural unit of compact bone? canaliculus Haversian canal osteoid osteon

Osteon (Haversian system) consists of central canal, lamellae (rings), lacunae, osteocytes and canaliculi The structural unit of compact bone is the osteon, an elongated cylinder oriented parallel to the long axis of the bone.

Which of the following correctly pairs the structure at C with its primary component? endosteum; dense regular connective tissue periosteum; dense irregular connective tissue periosteum; cuboidal epithelium endosteum; areolar tissue

Periosteum; dense irregular connective tissue The periosteum is composed of dense irregular connective tissue along with a layer of simple squamous epithelium.

Which of the following statements is true? Osteoclasts are important in removing calcium from the blood stream. Bone would be more brittle with more collagen in the matrix. The red marrow in the medullary cavity produces our red blood cells. Spongy bone is well adapted to accept stress in many directions, which makes it good for shock absorption.

Spongy bone is well adapted to accept stress in many directions, which makes it good for shock absorption. While not as strong as compact bone, spongy bone is a great shock absorber.

Costal cartilages join most ribs to the sternum. True or False

True

Flat bones consist of spongy bone sandwiched between compact bone. Is this statement true or false? True False

True Flat bones consist of two thin plates of compact bone enclosing a spongy bone layer.

The collagen in the osteoid bone matrix makes the overall bone matrix stronger by allowing flexibility. Is this statement true or false? True False

True The matrix is one-third organic osteoid. This portion includes a large amount of collagen that allows the bone to stretch and absorb shock without being too brittle.

D The shaft of an adult long bone is composed of compact bone.

Which of the labeled parts of the bone is composed primarily of compact bone?

The canal that runs through the core of each osteon (the Haversian canal) is the site of ________. a) cartilage and interstitial lamellae b) osteoclasts and osteoblasts c) yellow marrow and spicules d) blood vessels and nerve fibers

d) blood vessels and nerve fibers

Which of the following cells are NOT matched with its appropriate function? osteoclasts; bone reabsorption osteocytes; produce new bone cells. osteoblasts create new bone matrix bone lining cells; maintain matrix

osteocytes; produce new bone cells. Osteocytes are mature bone cells that monitor and repair mature bone tissues.

What is the weakest part of a developing, adolescent long bone? the epiphyseal plate the medullary cavity the epiphyses the diaphysis

the epiphyseal plate The epiphyseal plate is a weak point because of the lack of calcification.