Chapter 6 Homework Review

At which point during embryonic development can most of the bones of the adult skeleton be identified? -10 weeks -4 weeks -8 weeks -16 weeks

16 weeks

The correct order for these events is The following are major steps in the process of intramembranous ossification. 1. Clusters of osteoblasts form osteoid that becomes mineralized. 2. Osteoblasts differentiate within mesenchymal connective tissue. 3. Spicules of bone radiate out from the ossification centers. 4. Mesenchymal cells aggregate. The correct order for these events is 4, 2, 1, 3. 4, 1, 2, 3. 2, 3, 1, 4. 2, 1, 3, 4.

4, 2, 1, 3.

When production of sex hormones increases at puberty, epiphyseal plates -Accelerate rapidly, but mostly in thickness. -Are hardly affected. -Get wider. -Become narrower. -Increase slowly.

Become narrower

C cells of the thyroid gland secrete which of the following? -Calcitonin -Calcium -Calcitriol -PTH

Calcitonin

Which of the following hormones is currently thought to decrease plasma calcium levels in pregnant women and children? -Calcitonin -Calcitriol -Thyroid hormones -Parathyroid hormone (PTH)

Calcitonin

Elevated levels of calcium ion in the blood stimulate the secretion of the hormone: -Testosterone. -Thyroid hormone. -Calcitonin. -Parathyroid hormone. -Growth hormone.

Calcitonin.

To form perforating fibers, osteoblasts from the periosteum cement collagen fibers from tendons, ligaments, and joint capsules into which structures? To form perforating fibers, osteoblasts from the periosteum cement collagen fibers from tendons, ligaments, and joint capsules into which structures? -Interstitial lamellae -Circumferential lamellae -Concentric lamellae -Central canal

Circumferential lamellae

________ fractures are completely internal; they do not break through the skin. -Closed -Open -Compound -Both closed and recurrent -Recurrent

Closed

Which type of fracture occurs in vertebrae that are subjected to extreme stresses? -Colles fracture -Epiphyseal fracture -Pott fracture -Compression fracture

Compression fracture

The smooth, rounded articular process of a bone is termed a -Trochlea. -Condyle. -Crest. -Head. -Ridge.

Condyle.

Osteoprogenitor cells are not/do not: -Present in small numbers in the lining of passageways that penetrate the matrix of compact bone. -Important in the repair of a fracture. -Divide to produce daughter cells that differentiate into osteoclasts. -Mesenchymal cells present in small numbers in the inner, cellular layer of the periosteum.

Divide to produce daughter cells that differentiate into osteoclasts.

What type of bone growth is the doctor most likely looking for in the example above? -Endochondral ossification -Appositional ossification -Ossification and remodeling around an external callus -Intramembranous ossification

Endochondral ossification

Ectopic bones may occur in which of the following conditions? -Gigantism -FOP -Marfan syndrome -Acromegaly

FOP

Excessive growth hormone prior to puberty could result in -gigantism. -dwarfism. -osteoporosis. -osteopenia. -rickets.

Gigantism

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 osteoblasts on bone -Increase reabsorption of calcium in the kidney -Increase osteoclasts

Increase osteoblasts on bone

Which is not a characteristic of periosteum? -It actively participates in bone growth and repair. -It has two layers, an inner layer and an outer layer. -It is an incomplete cellular layer that lines the medullary cavity. -It provides a route for the blood and nervous supply.

It is an incomplete cellular layer that lines the medullary cavity.

The humerus is an example of a(n) ________ bone. -Irregular -Flat -Sesamoid -Long -Short

Long

Which condition, due to excessive cartilage formation at the epiphyseal cartilages, results in individuals who are very tall, with long, slender limbs? -Marfan syndrome -Gigantism -Acromegaly -Achondroplasia

Marfan syndrome

Which vessel supplies the articular cartilage of long bones? -Epiphyseal artery -Nutrient artery -Metaphyseal artery -None. It is avascular.

None. It is avascular.

The process of osteolysis is performed by which cell population? -Osteocytes -Osteoblasts -Osteoprogenitor cells -Osteoclasts

Osteoclasts

Which component is not present in spongy bone? -Osteons -Lamellae -Trabeculae -Canaliculi

Osteons

Decreased calcium levels in the bloodstream occur as a result of all of the following except: -Increased calcitonin levels. -Decreased PTH or calcitriol levels. -PTH stimulation of osteoclasts. -Calcitonin inhibition of osteoclasts.

PTH stimulation of osteoclasts.

A fracture at the ankle involving both lower leg bones is often called a ________ fracture. -Pott -displaced -Colles -greenstick -compression

Pott

The cartilage the doctor is referring to will disappear when? -The osteoblasts work faster than cartilage producing cells -Mesenchymal cells cluster around ossification centers -Chondrocytes accelerate their activities in the bone -The cartilage deteriorates and is eliminated

The osteoblasts work faster than cartilage producing cells

Which structural features of spongy bone are oriented along stress lines and are cross-braced extensively? -Perforating canals -Trabeculae -Concentric lamellae -Canaliculi

Trabeculae

Parathyroid hormone functions in all of the following ways, except that it DOES NOT: -increase the level of calcium ions in the blood. -directly inhibit calcitonin secretion. -mobilize calcium from bone. -enhance the reabsorption of calcium at the kidneys. -stimulate osteoclast activity.

directly inhibit calcitonin secretion.

After a fracture of the diaphysis has healed, the thickened region that results is called the -Epiphyseal plate. -Fracture facet. -Dense tuberosity. -External callus. -Condyle.

external callus.

The following are important steps in the process of endochondral ossification. 1. Enlarged chondrocytes die. 2. Osteoblasts replace calcified cartilage with spongy bone. 3. Chondrocytes enlarge and the surrounding matrix begins to calcify. 4. Blood vessels penetrate the cartilage. 5. Perichondrial cells become osteoblasts and produce a thin shell of bone. The correct order for these events is -3, 1, 5, 4, 2. -1, 5, 3, 4, 2. -3, 1, 4, 5, 2. -2, 3, 1, 5, 4. -1, 3, 5, 4, 2.

3, 1, 5, 4, 2.

Which is the last phase of endochondral ossification? -A primary ossification center is formed. -Chondrocytes near the center of the shaft increase greatly in size. -An epiphyseal cartilage separates the epiphysis from the diaphysis. -A secondary ossification center is formed.

An epiphyseal cartilage separates the epiphysis from the diaphysis.

In appositional bone growth, how are layers of compact bone added to the bone's outer surface? -Bone is deposited by superficial osteoblasts. -Bone matrix is removed by osteoblasts. -Bone is deposited by superficial osteoclasts. -Additional interstitial lamellae are deposited, and the bone continues to increase in diameter.

Bone is deposited by superficial osteoblasts

Which of the following is formed by intramembranous ossification? -Roof of the skull -Femur -Both the roof of the skull and the clavicle -Clavicle -Carpal bones

Both the roof of the skull and the clavicle

PTH promotes the formation of which hormone? -Vitamin D -Calcitonin -Thyroid hormones -Calcitriol

Calcitriol

Which hormone works directly in the intestine to increase plasma calcium levels? -Calcitonin -Parathyroid hormone (PTH) -Calcitriol

Calcitriol

The most abundant mineral in the human body is -potassium. -phosphorus. -hydrogen. -sodium. -calcium.

Calcium

The intestinal response to PTH stimulation is which of the following? -Calcium is absorbed slowly. -Calcium is released. -Calcium is conserved. -Calcium is absorbed quickly.

Calcium is absorbed quickly.

Which of the following accounts for almost two-thirds of the weight of bone? -Calcium phosphate -Calcium hydroxide -Collagen fibers -Calcium carbonate

Calcium phosphate

Which bone is not formed via intramembranous ossification? -Mandible -Femur -Patella -Clavicle

Femur

A rounded hole through a bone is termed a -Facet. -Foramen. -Linea. -Ramus. -Tubercle.

Foramen

Which of the following describes spiral fractures? -Fractures that are produced by twisting stresses that spread along the length of the bone -Fractures that break the bone shaft across its long axis -Fractures that produce new and abnormal bone arrangements -Fractures in which only one side of the shaft is broken and the other is bent

Fractures that are produced by twisting stresses that spread along the length of the bone

What characteristic may cause life-threatening issues in individuals with Marfan syndrome? -Genetic mutation that affects the structure of connective tissue throughout the body -Overproduction of growth hormone -Genetic mutation that involves the deposition of bone around skeletal muscles -Abnormal epiphyseal activity

Genetic mutation that affects the structure of connective tissue throughout the body

Remnants of osteons whose matrix components have been almost completely recycled by osteoclasts are known as which of the following? -Circumferential lamellae -Perforating canals -Concentric lamellae -Interstitial lamellae

Interstitial lamellae

In intramembranous ossification, which cells first cluster together and start to secrete the organic components of the matrix? -Chondrocytes -Mesenchymal cells -Osteoprogenitor cells -Osteocytes

Mesenchymal cells

In what area of a long bone would it probably be easiest to observe the cartilage the orthopedic doctor refers to? -Nutrient foramen -Surface of epiphysis at articulations -Medullary cavity -Metaphysis

Metaphysis

Ankle fractures that affect both bones of the leg are called: -Transverse fractures. -Colles fractures. -Displaced fractures. -Pott fractures.

Pott fractures

A lack of exercise could: -Cause bones to become longer. -Result in porous and weak bones. -Cause bones to lose their medullary cavity. -Cause bones to become thicker. -Cause bones to store more calcium.

Result in porous and weak bones.

Which of the following statements about Marfan's syndrome is false? -results in short, stubby fingers -results from a mutation -affects epiphyseal cartilages -affects connective tissue genes -none of the above

Results in short, stubby fingers

Bones that develop within tendons are called ________ bones. -Irregular -Sesamoid -Tendon -Sutural -Wormian

Sesamoid

Which class of bones develops inside tendons and is most commonly located near joints at the knees, the hands, and the feet? -Flat bones -Sesamoid bones -Short bones -Sutural bones

Sesamoid bones

Small, oddly shaped bones that fill gaps between bones of the skull are called ________ bones. -Tendon -Sutural -Irregular -Sesamoid -Sagittal

Sutural

How would removing hydroxyapatite from bone matrix affect the physical properties of a bone? -The bone would be more brittle. -The bone would be less compressible. -The bone would be stronger. -The bone would be less flexible. -The bone would be more flexible.

The bone would be more flexible.

Which of the following is not a surface feature of the pelvis? -Trochanter -Spine -Line -Fossa

Trochanter

Which surface feature is a smooth, grooved articular process shaped like a pulley? -Trochanter -Tuberosity -Trochlea -Tubercle

Trochlea

Which of following is a function of the skeletal system? -protection of internal organs -blood cell production -body support -calcium homeostasis -all of the above

all of the above

The hormone calcitonin functions to -decrease the rate of calcium absorption. -decrease the rate of calcium excretion -stimulate osteoclast activity. -decrease the level of calcium ion in the blood. -stimulate osteoblasts and osteoclasts.

decrease the level of calcium ion in the blood.

A rib is an example of a ________ bone. -sutural -flat -long -sesamoid -short

flat

A deep hollow on a bone is termed a -sulcus. -fossa. -line. -fissure. -facet.

fossa

The periosteum contains all of the following except: -Blood vessels. -Sensory nerves. -Lymphatic vessels. -Motor nerves.

motor nerves.

The carpal bones are examples of ________ bones. -short -sesamoid -flat -irregular -long

short

Which of the following bones is classified as "irregular" in shape? -frontal -ulna -metatarsal -vertebra -patella

vertebra