Mastering A&P: Anatomy and Physiology Unit Two Chapter Six
osteoblasts begin producing bone faster than chondrocytes are producing new epiphyseal cartilage.
At puberty: -decreasing thyroid hormones stimulate bone growth dramatically. -chondrocytes begin producing bone faster than osteoblasts are producing new epiphyseal cartilage. -epiphyseal cartilage thickens. -osteoblasts begin producing bone faster than chondrocytes are producing new epiphyseal cartilage.
circumferential lamellae
To form perforating fibers, osteoblasts from the cellular layer of the periosteum cement collagen fibers from tendons, ligaments, and joint capsules into which structures? -concentric lamellae -interstitial lamellae -central canal -circumferential lamellae
osteons
Which component is not present in spongy bone? -canaliculi -lamellae -trabeculae -osteons
osteoclast activity when calcitonin is absent
Which is greater? -osteoclast activity when calcitonin is present -osteoclast activity when calcitonin is absent
tendons
Which of the following are not components of the skeletal system? -bones -tendons -ligaments -cartilages
sinus
A chamber within a bone normally filled with air is a -sinus. -facet. -fissure. -meatus. -sulcus.
fossa
A shallow depression on a bone is termed a -sulcus. -fossa. -fissure. -facet. -line.
It is an incomplete cellular layer that lines the medullary cavity.
All of the following are characteristics of periosteum except: -It actively participates in bone growth and repair. -It has two layers, an inner layer and an outer layer. -It provides a route for the blood and nervous supply. -It is an incomplete cellular layer that lines the medullary cavity.
PTH stimulation of osteoclasts.
All of the following result in decreased calcium levels in the bloodstream, except: -calcitonin inhibition of osteoclasts. -decreased PTH or calcitriol levels. -increased calcitonin levels. -PTH stimulation of osteoclasts.
the primary ossification center in the diaphysis
As blood vessels extend into the spaces left by dying chondrocytes, the models begin to ossify internally. Where does internal ossification begin? -the epiphyseal lines -the primary ossification centers in the epiphyses -the primary ossification center in the diaphysis -the secondary ossification centers in the epiphyses
calcium.
Bone plays a central role in the regulation of blood levels of -potassium. -sodium. -calcium. -iron. -sulfate.
osteoblasts and begin to deposit bone matrix
Cells of the perichondrium need to take on a new role as ossification begins. They will become __________. -new chondrocytes, so the model can continue to grow -fibroblasts, to coat the model in collagen -osteoblasts and begin to deposit bone matrix -osteoclasts and dissolve cartilage matrix
bones grow wider.
During appositional growth, -bone is replaced by cartilage. -bones grow longer. -the epiphysis fuses with the diaphysis. -osteoblasts are overwhelmed by osteocytes. -bones grow wider.
FOP
Ectopic bones may occur in which of the following conditions? -gigantism -acromegaly -Marfan syndrome -FOP
calcitonin.
Elevated levels of calcium ion in the blood stimulate the secretion of the hormone -calcitonin. -thyroid hormone. -growth hormone. -parathyroid hormone. -testosterone.
cartilage model.
Endochondral ossification begins with the formation of a(n) -osteoblasts model. -cartilage model. -calcified model. -fibrous connective-tissue model. -membranous model.
giantism.
Excessive growth hormone prior to puberty could result in -osteopenia. -dwarfism. -osteoporosis. -giantism. -rickets.
medullary cavity
Fat is stored within the -metaphysis. -diaphysis. -spongy bone. -medullary cavity. -epiphysis.
Bone is deposited by superficial osteoblasts.
In appositional bone growth, how are layers of compact bone added to the bone's outer surface? -Bone is deposited by superficial osteoblasts. -Bone is deposited by superficial osteoclasts. -As additional interstitial lamellae are deposited, and the bone continues to increase in diameter. -Bone matrix is removed by osteoblasts.
hydroxyapatite.
In bone, the calcium phosphate forms crystals of -hydroxyapatite. -calcium carbonate. -calcium apatite. -osteocyte. -carbonite.
mesenchymal cells
In intramembranous ossification, which cells first cluster together and start to secrete the organic components of the matrix? -chondrocytes -osteoprogenitor cells -osteocytes -mesenchymal cells
parallel.
In relationship to the diaphysis of a long bone, the osteons are -diagonal. -proximal. -parallel. -radial. -anterior.
inhibits calcitonin secretion
Parathyroid hormone functions in all of the following ways except that it -stimulates osteoclast activity. -raises the level of calcium ion in the blood. -inhibits calcitonin secretion. -decreases the rate of calcium excretion. -increases the rate of calcium absorption.
short
The carpal bones are examples of ________ bones. -irregular -long -flat -short -sesamoid
3, 1, 5, 4, 2
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. What is the correct order for these events? -1, 5, 3, 4, 2 -2, 3, 1, 5, 4 -1, 3, 5, 4, 2 -3, 1, 5, 4, 2 -3, 1, 4, 5, 2
trabeculae.
The interconnecting tiny arches of bone tissue found in spongy bone are called -lacunae. -concentric lamellae. -osteons. -trabeculae. -interstitial lamellae.
osteons.
The structural units of mature compact bone are called -lamellae. -canaliculi. -lacunae. -osteons. -osteocytes.
Osteoclasts
________ free calcium from bone to maintain blood calcium levels. -Osteocytes -Osteoclasts -Osteogenic cells -Osteoblasts
Her epiphyseal plates have ossified.
Bill, age 15, is still growing, but his older sister Andrea, age 19, has stopped. What has changed in Andrea's bones? -They have more cartilage than Bill's. -Her osteoblasts have died. -Sex hormones are no longer telling them to grow. -Her epiphyseal plates have ossified.
sesamoid
Bones that develop within tendons are called ________ bones. -tendon -sesamoid -Wormian -sutural -irregular
calcitonin
C cells of the thyroid gland secrete which of the following? -calcium -calcitriol -calcitonin -PTH
osteoblasts.
Cells that secrete the organic components of the bone matrix are called -chondrocytes. -osteoprogenitor cells. -osteoclasts. -osteoblasts. -osteocytes.
ossification
During the process of ________, an existing tissue is replaced by bone. -appositional growth -osteolysis -ossification -deposition -perforation
blood vessels.
The central canal of an osteon contains -osteocytes. -lacunae. -bone marrow. -blood vessels. -concentric lamellae.
4, 1, 2, 3
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. What is the correct order for these events? -2, 3, 1, 4 -4, 2, 1, 3 -4, 1, 2, 3 -2, 1, 3, 4
decrease the level of calcium ion in the blood.
The hormone calcitonin functions to -decrease the rate of calcium excretion. -stimulate osteoblasts and inhibit osteoclasts. -stimulate osteoclast activity. -decrease the level of calcium ion in the blood. -decrease the rate of calcium absorption.
absorbed quickly.
The intestinal response to PTH secretion when calcium ion levels are low is that calcium is -released. -excreted. -conserved. -absorbed quickly. -absorbed slowly.
trochanter
The large proximal projection on the femur is termed the -condyle. -tuberosity. -trochanter. -tubercle. -ramus.
endosteum.
The lining of the medullary cavity is called the -perichondrium. -perimysium. -endosteum. -epimysium. -periosteum.
marrow
The medullary cavity of bones contains -cartilage. -compact bone. -periosteum. -marrow. -osteons.
calcium
The most abundant mineral in the human body is -hydrogen. -potassium. -phosphorus. -calcium. -sodium.
canaliculi.
The narrow passageways that contain cytoplasmic extensions of osteocytes are called -medullary cavities. -lacunae. -foramina. -central canals. -canaliculi.
neck
The narrow region between the head and shaft of a long bone is called the -canal. -sulcus. -trochlea. -ramus. -neck.
motor nerves
The periosteum contains all of the following except: -blood vessels. -motor nerves. -lymphatic vessels. -sensory nerves.
lacuna
The space occupied by an osteocyte is called a -lacuna. -Venetian canal. -Haversian canal. -trabecula. -Volkmann's canal.
genetic mutation that affects the structure of connective tissue throughout the body
What characteristic may cause life-threatening issues in individuals with Marfan syndrome? -overproduction of growth hormone -genetic mutation that involves the deposition of bone around skeletal muscles -genetic mutation that affects the structure of connective tissue throughout the body -abnormal epiphyseal activity
epiphyseal cartilages
What structure allows a bone to grow in length? -lacunae -trabeculae -metaphysis -periosteal bud -epiphyseal cartilages
synovial fluid
What supplies the articular cartilage of long bones with oxygen and nutrients? -epiphyseal artery -nutrient artery -metaphyseal artery -synovial fluid
femur
Which bone is not formed via intramembranous ossification? -mandible -patella -clavicle -femur
sesamoid bones
Which class of bones develops inside tendons and is most commonly located near joints at the knees, the hands, and the feet? -sesamoid bones -short bones -sutural bones -flat bones
Marfan syndrome
Which condition, due to excessive cartilage formation at the epiphyseal cartilages, results in individuals who are very tall, with long, slender limbs? -acromegaly -achondroplasia -gigantism -Marfan syndrome
blood calcium levels when parathyroid hormone is increased
Which is greater? -blood calcium levels when parathyroid hormone is decreased -blood calcium levels when parathyroid hormone is increased
mature bone cell
Which of the following best matches osteocyte? -secretes organic matrix -mature bone cell -stem cell -dissolves matrix
vertebra
Which of the following bones is classified as "irregular" in shape? -frontal -patella -metatarsal -vertebra -ulna
All of the answers are correct
Which of the following is a function of the skeletal system? -calcium homeostasis -body support -blood cell production -protection of internal organs -All of the answers are correct.
chondroitin sulfate
Which of the following is not present in bone? -calcium carbonate -calcium phosphate -chondroitin sulfate -hydroxyapatite -collagen fibers
Calcium is absorbed quickly.
Which of the following is the intestinal response to PTH stimulation? -Calcium is absorbed slowly. -Calcium is released. -Calcium is conserved. -Calcium is absorbed quickly.
It results in short, stubby fingers.
Which of the following statements about Marfan's syndrome is false? -It affects epiphyseal cartilages. -It affects connective tissue genes. -It results from a mutation. -It results in short, stubby fingers. -None of the answers is correct.
Osteoprogenitor cells
________ are mesenchymal cells that develop into osteoblasts. -Osteoprogenitor cells -Osteoclasts -Osteocytes -Osteomedullary cells -Squamous osteons
Collagen fibers
________ are stronger than steel when stretched. -Mesenchymal cells -Collagen fibers -Lamellae -Hydroxyapatite cells -Lacunae
Spongy
________ bone reduces the weight of the skeleton and reduces the load on muscles. -Compact -Long -Short -Spongy -Irregular