A&P 1 chapter 6
In which of the following does bone replace existing cartilage?
Endochondral ossification
The presence of which structure is a clear indication that the person has reached their adult height and has stopped growing?
Epiphyseal line
At maturity, why are women generally shorter than men?
Estrogen promotes faster closure of epiphyseal plates than androgen does.
Spongy bone is found primarily at which part of long bones?
Expanded ends, where long bones articulate with other skeletal elements
What is a potential problem that can arise from the continual remodeling of bone matrix?
Incorporation of heavy metals into the bone matrix
Which of the following is false regarding vitamin C and bone health?
It can also be produced in the skin.
What is not a major advantage of bones undergoing continual remodeling?
It can continue to lengthen bones throughout life.
Which of the following statements about bone tissue is FALSE?
It is made primarily of cells.
The humerus and the femur are examples of what shape of bone?
Long bones
A tall, slender person with unusually long, slender limbs because of excess cartilage formation at the epiphyseal cartilages has what disorder?
Marfan's syndrome
What type of tissue is replaced by bone in intramembranous ossification?
Mesenchyme or embryonic fibrous connective tissue
Calcium is a very important substance for the proper functioning of various body systems. Which function of the skeletal system helps maintain calcium homeostasis?
Mineral storage
Which of the following types of bone cells are responsible for removing and recycling bone?
Osteoclasts
What condition accelerates after menopause because of a decline in circulating estrogen?
Osteoporosis
What is the term for a reduction in bone mass that is large enough to compromise the normal function of bone?
Osteoporosis
If the level of calcium in the blood drops below normal levels, which hormone is produced to correct this homeostatically?
Parathyroid hormone
A fracture of the ankle where both the distal ends of the tibia and fibula broken is called a ________ fracture.
Pott's
Shielding the soft organs like the brain, spinal cord, and heart with its hard, strong matrix is an example of which function of the skeletal system?
Protection
Which component of bone is responsible for blood cell formation?
Red bone marrow
What is the term for the process in which the organic and mineral components of bone are continuously recycled and renewed?
Remodeling
Which of the following is an effect of stress on a bone?
The bone will become thicker.
How is the tendon connected to a bone so that it will withstand the force that must be applied by the muscle to move the bone?
The collagen fibers of the tendon as well as the periosteum are incorporated into the bone tissue.
A person who chooses to eat a diet of junk food and has a sedentary job is NOT likely to experience which of the following?
Thickened, prominent ridges on bones in places of muscle attachment
Which of the following are NOT structural components of compact bone?
Trabeculae
__________ is required for collagen synthesis, and a deficit of it results in a condition called scurvy.
Vitamin C
Which vitamin(s) is/are specifically required for normal bone growth?
Vitamins A, B12, C, D, and K
Which component of the bone stores energy?
Yellow marrow
The result of overproduction of growth hormone after puberty can result in a condition called ___________.
acromegaly
Appositional growth on the outer surface of bones results in __________.
an increase in the diameter of a growing bone
Darcy wrecks her bike and experiences a break in the distal portion of her radius, which now projects out of her skin. Which type of fracture does she have?
an open Colles' fracture
The basic functional unit(s) of compact bone tissue is/are _____________.
an osteon
Unlike compact bone, spongy bone (also called cancellous bone) resembles a network of bony struts separated by spaces that are normally filled with __________.
bone marrow
The hormone synthesized in the kidneys that regulates absorption of calcium and phosphate ions in the digestive tract is __________.
calcitriol
Osteomalacia results from a diet deficient in __________.
calcium or vitamin D
Narrow passageways that allow osteocytes to communicate with neighboring osteocytes are called _____________.
canaliculi
The small passageways that exist in the bone matrix to allow living bones cells to obtain nutrients and get rid of wastes are called __________.
canaliculi
The region known as the epiphyseal plate is the area where __________.
cartilage is not replaced by bone until after puberty
Fractures that shatter a bone into many small fragments are called __________ fractures.
comminuted
The type of fracture that occurs in vertebrae that are subject to extreme stresses is a __________ fracture.
compression
A large, rounded, articulating process of bone is a _________.
condyle
The endosteum is found in all of the following places except the __________.
covering the outside surface of the bones
A prominent ridge where ligaments or tendons attach to the bone is called a __________.
crest
Thin bones that form the roof of the skull, the sternum, and the scapulae are considered ________.
flat bones
Which anatomical term describes a rounded passageway for blood vessels or nerves?
foramen
The result of overproduction of growth hormone before puberty can result in a condition called ___________.
gigantism
A fracture in which one side of the shaft is broken and the other side is bent is a __________.
greenstick fracture
When cartilage is produced at the epiphyseal side of the metaphysis at the same rate as bone is deposited on the opposite side, bones __________.
grow longer
What are the hormones that stimulate bone growth?
growth hormone and thyroxine
Where is a sesamoid bone most often found?
near joints at the knees, the hands, and the feet
A fracture that results in the bone penetrating through the skin is called a(n) _______ fracture.
open
Which of the following is the term for a fracture in which the broken bone breaks through the skin?
open or compound
The process of replacing other tissues with bone is called __________.
ossification
A girl born with nonfunctioning ovaries could be expected to have a deficiency in the activity of which type of cell?
osteoblasts
Cells that produce new bone matrix are called __________.
osteoblasts
As osteoclasts absorb and remove bone matrix, they leave shallow depressions called a(n) _________.
osteoclastic crypt
Giant, multinucleated cells involved in the process of osteolysis are __________
osteoclasts
Mature bone cells found in lacunae are called __________.
osteocytes
Even as an adult, we have populations of primitive cells that can produce osteoblasts. These primitive cells are called __________.
osteogenic cells
The process of bone breakdown or erosion is called __________.
osteolysis
What is the condition that is caused by inadequate ossification as a natural consequence of aging?
osteopenia
Canals that extend perpendicularly through bone to supply blood to deeper osteons and to tissues of the medullary cavity are ___________________ canals.
perforating
In endochondral ossification, blood vessels penetrate and invade the central region of the cartilaginous model. This first area that is invaded is called the __________.
primary ossification center
A general term for a bony projection, often where a muscle, tendon, or ligament attaches to a bone is called a _______.
process
One function of bone is to produce red and white blood cells. These cells are made in what substance in bone?
red marrow
Homogenized milk fortified with vitamin D is effective in preventing what bone disorder in children?
rickets
The condition in which a child's leg bones bend under the weight of the body is called __________.
rickets
The carpals or wrist bones are examples of _____
short bones
A chamber within in a bone, normally filled with air, is a ___________
sinus
The bony skeleton begins to form about __________ after fertilization and usually does not stop growing until about age __________ years.
six weeks; 25
The fibers of tendons intermingle with those of the periosteum, attaching __________.
skeletal muscles to bones
The thyroid gland regulates bone growth and maintenance through its production of what hormone?
thyroxine
The meshwork of supporting bundles of fibers that make up spongy bone are __________.
trabeculae
A fracture that results in the break of a bone across the long axis of the shaft is called a _________ fracture.
transverse
A smooth, grooved articulating process of bone shaped like a pulley is a ___________.
trochlea
A muscle attachment site, which appears as a slightly raised and roughened area on the bone is called a __________.
tuberosity
Which of the following bones is accurately described as an irregular bone?
vertebra
Depressions, grooves, and tunnels in bone indicate locations __________.
where blood vessels or nerves lay alongside or penetrated bones
Changing the magnitude and direction of forces generated by skeletal muscles is an illustration of the skeletal function of __________.
leverage
The narrow zone that connects the epiphysis and the diaphysis of long bones is the _________.
metaphysis
Which of the following does NOT occur during fracture repair?
Dead tissue next to the break is left in the break area and is covered by new bone tissue.
Which of the following is not brought about by parathyroid hormone?
Decreased production of calcitriol
Which of the following functions of the skeletal system is not facilitated by the bone's hard and strong extracellular matrix?
Blood cell production
Which bones are not formed by intramembranous ossification?
Bones of the appendages
Bone stores ____% of body's calcium and phosphate.
99
Which statement concerning endochondral ossification is the most accurate?
A primary ossification center begins replacing cartilage in the central region of the cartilage rod.
Which of the following is not a function of the skeletal system?
Contraction
If an abnormal rearrangement or alignment of the bones results from a fracture, it is called a __________ fracture.
displaced
The term for the expanded end of a long bone where the joint surfaces are located is the __________.
epiphysis
An expanded joint surface shaped like a ball and found on the articular end of the epiphysis is called a _______
head
Abnormal development of bone in non-skeletal tissues is called _____________ ossification.
heterotopic
Two-thirds of a bone's weight is composed of calcium phosphate which interacts with calcium hydroxide to form crystals of __________.
hydroxyapatite
Calcitonin does all of the following except ___________.
increase osteoblast activity
Parathyroid does all of the following except __________.
increase the activity of osteoblasts
Appositional growth __________
increases the diameter of a long bone, forms circumferential lamellae, and involves both osteoblasts and osteoclasts
When the calcium ion concentration of the blood rises above the normal level, secretion of the hormone calcitonin __________.
increases the rate of calcium ion excretion from the kidneys
The outer dense connective tissue of a bone, the periosteum, ________.
isolates the bone from surrounding tissues, provides a route for circulatory and nervous supply, and actively participates in bone growth and repair
Osteopenia, the inadequate ossification process that occurs with age, especially affects bone mass in all of the following sites, except the______________.
knee
The spaces in the bony matrix where osteocytes exist are ____________.
lacunae
Compact bone is characterized by many cylindrical osteons. Osteons are formed by layers of nested cylinders each called a(n) _____________.
lamella
Small, flat, irregularly shaped bones found between the flat bones of the skull are called ________
sutural bones.
