137 terms

A& P Test #3

Blood cell formation occurs in
red bone marrow
Two-thirds of the weight of bone is accounted for by
crystals of calcium phosphate
The membrane found wrapping the bones, except at the joint cavity, is the
The basic functional unit of compact bone is the Haversian system or
The vitamins essential for normal adult bone maintenance and repair are
C and D
The hormones that coordinate the storage, absorption, and excretion of calcium ions are
calcitonin and parathyroid hormone
The presence of an epiphyseal line indicates
epiphyseal growth has ended
The primary reason that osteoporosis accelerates after menopause in women is
reduced levels of circulating estrogens
The nonpathologic loss of bone that occurs with aging is called
What are the five primary functions of the skeletal system?
support, storage of minerals and lipids, blood cell production, protection, and leverage
List the four distinctive cell populations of osseous tissue.
osteocytes, osteoblasts, osteoclasts, and osteoprogenitor cells
What are the primary parts of a typical long bone?
diaphysis (shaft), epiphysis, epiphyseal cartilage/line, articular cartilage, medullary canal, periosteum, and endosteum
What is the primary difference between endochondral ossification and intramembraneous ossification?
In intramembraneous ossification, bone develops from mesenchyme or fibrous connective tissue. In endochondral ossification, bone develops from a cartilage model.
List the organic and inorganic components of bone matrix.
organic = collagen; inorganic = hydroxyapatite crystals
What nutritional factors are essential for normal bone growth and maintenance?
calcium salts, phosphate salts, and vitamins A, C, and D3
What hormonal factors are necessary for normal bone growth and maintenance?
calcitiriol, growth hormone, thyroxine, estrogens (in females) or androgens (in males), calcitonion, and parathyroid hormone (PTH)
Which three organs or tissues interact to assist in the regulation of calcium ion concentration in body fluids?
the bones, the intestinal tract, and the kidneys
What major effects of parathyroid hormone oppose those of calcitonin?
Parathyroid hormone stimulates osteoclast activity, increases the rate of intestinal absorption of calcium ions, and decreases the rate of excretion of calcium ions
If spongy bone has no osteons, how do nutrients reach the osteocytes?
Nutrients reach the osteocytes in spongy bone by diffusing along canaliculi that open onto the surface of the trabeculae.
Why are stresses or impacts to the side of the shaft in a long bone more dangerous than stress applied to the long axis of the shaft?
The osteons are aligned parallel to the long axis of the shaft, which does not bend when forces are applied to either end. Stresses or impacts to the side of the shaft can lead to a fracture.
Why do extended periods of inactivity cause degenerative changes to the skeleton?
The lack of stress during inactivity leads to the removal of calcium salts from bones. Up to one-third of the bone mass can be lost in this manner, causing the bones to become thin and brittle.
What are the functional relationships between the skeleton, on the one hand, and the digestive and urinary systems, on the other?
The digestive and urinary systems (kidneys) play important roles in providing the calcium and phosphate minerals needed for bone growth. In return, the skeleton provides protection and acts as a reserve of calcium, phosphate, and other minerals that can compensate for changes in the dietary supplies of these ions.
Why would a physician concerned about the growth patterns of a young child request an x-ray on the hand?
There are many long bones in the hand, each of which has an epiphyseal cartilage (plate). Measuring the width of these plates will provide clues to the hormonal control of growth in the child.
Why does a second fracture in the same bone tend to occur at a site different from that on the first fracture?
Once a bone fracture has been repaired, the bone tends to be stronger and thicker than normal at the fracture site.
The process of bone growth at the epiphyseal cartilage is similar to
endochondral ossification
How might bone markings be useful in identifying the remains of an individual who was shot and killed years ago?
Bone markings give clues as to the size, age, sex, and general appearance of an individual.
While playing on her swing set, 10-year-old Sally falls and breaks her right leg. At the emergency room, the doctor tells her parents that the proximal end of the tibia where the epiphysis meets the diaphysis is fractured. The fracture is properly set and eventually heals. During a routine physical when she is 18, Sally learns that her right leg is 2 cm shorter than her left, probably because of her accident. What might account for this difference?
The fracture might have damaged the epiphyseal cartilage in Sally's right leg. Even though the bone healed properly, the damaged leg did not produce as much cartilage as did the undamaged leg. The result would be a shorter bone on the side of the injury.
Which of the following conditions would you possibly observe in a child who is suffering from rickets?
bowed legs
Frank does not begin puberty until he is 16. What effect would you predict this will have on his stature?
Frank will probably be taller than if he had started puberty earlier.
In physical anthropology, cultural conclusions can be drawn from a thorough examination of the skeletons of ancient peoples. What sorts of clues might bones provide as to the lifestyles of those individuals?
The matrix of bone will absorb traces of minerals from the diet. These minerals can be identified hundreds of years later. A diet rich in calcium and vitamin B will produce denser bones than will a diet lacking these. Cultural practices such as the binding of appendages or the wrapping of infant heads will manifest in misshapen bones. Heavy muscular activity will result in larger bone markings, indicating an athletic lifestyle.
What are the five primary functions of skeletal system?
support, storage of minerals and lipids, blood cell production, protection, and leverage
List the four distinctive cell population of osseous tissue.
osteocytes, osteoblasts, osteoclasts, and osteoprogenitor cells
Describe the functioning of osteoblasts and osteoclasts.
osteoblasts: produce new bone matrix called osteogenesis by making new proteins osteoclasts: cells that remove and recycle bone matrix
Into what six categories are bones divided on the basis of shape?
long bones, flat bones, sutural bones, irregular bones, short bones and sesamoid bones
Distinguish between compact and spongy bone.
compact bone: have osteocytes that are arranged around the central canal that usually runs parallel to the surface of the bone; encounters stresses from a limited range of directions spongy bone: lamellae are not arranged in osteons; the matrix in spongy bone forms struts and plates called trabeculae; are lighter in weight
Describe the structure of compact and spongy bone.
compact bone: close knit collagen fibers with veins running through out the bone spongy bone: trabeculae and the canaliculi are spaced apart with openings on the surface and openings throughout the bone
What are the two types of bone marrow? Describe each type and its functions
red bone marrow: responsible for blood cell formation & yellow bone marrow: responsible for using adipose tissue as energy reserve
Describe the primary parts of a typical long bone.
structurally a long bone consists of a tubular shaft, the diaphysis, and an expanded area known as the epiphysis at each end, the diaphysis and epiphysis are connected at the metaphysic, the diaphysis consists of compact bone surrounding the marrow cavity, the epiphysis consists of spongy bone with a thin covering of compact bone
Describe the processes of intramembraneous and endochondral ossification.
Endochondral ossification- Step 1: As the cartilage enlarges, chondrocytes near the center of the shaft increase greatly in size. The matrix is reduced to a series of small struts that soon begin to calcify. The enlarged chondrocytes then die and disintegrate, leaving cavities within the cartilage. Step 2: Blood vessels grow around the edges of the cartilage, and the cells of the perichondrium convert to osteoblasts. The shaft of the cartilage then becomes ensheathed in a superficial layer of bone. Step 3: Blood vessels penetrate the cartilage and invade the central region. Fibroblasts migrating with the blood vessels differentiate into osteoblasts and begin producing spongy bone at a primary center of ossification. Bone formation then spreads along the shaft toward both ends. Step 4: Remodeling occurs as growth continues, creating a medullary cavity. The bone of the shaft becomes thicker, and the cartilage near each end epiphysis is replaced by shafts of bone. Further growth involves increasing in length and diameter. Step 5: Capillaries and osteoblasts migrate into the epiphyses, creating secondary ossification centers. Step 6: Soon the epiphyses are filled with spongy bone. An articular cartilage remains exposed to the joint cavity; over time it will be reduced to a thin superficial layer. Intramembraneous ossification- Step 1: Mesenchymal cells aggregate, differentiate into osteoblasts, and begin the ossification process. The bone expands as a series of spicules that spread into surrounding tissues. Step 2: As the spicules interconnect, they trap blood vessels within the bone. Step 3: Over time, the bone assumes the structure of spongy bone may later be removed, creating madullary cavities. Through remodeling, spongy bone formed in this way can ne converted to compact bone.
List the organic and inorganic components of the bone matrix. How do those components contribute to bone strength?
organic components are collagen and inorganic components are hydroxyapatite; the collagen fibers provide an organic framework on which hydroxyapatite crystals can form
Describe the regulation of calcium ions concentration in body fluid.
calcium ions are regulated by keeping a calcium concentration of 30 percent.
Why are stresses applied to the side of the shaft in a long bone more dangerous that stresses applied to the long axis of the shaft?
The osteons are aligned parallel to the long axis of the shaft, which does not bend when forces are applied to either end. Stresses or impacts to the side of the shaft can lead to a fracture.
Describe the periosteum and endosteum.
periosteum: a membrane with a fibrous outer layer and a cellular inner layer; isolates the bone from surrounding tissues, provides a route for the circulatory and nervous supply, and actively participates in bone growth and repair &endosteum: an incomplete cellular layer, lines the medullary cavity, which is active in bone growth, repair, and remodeling, and covers the trabeculae of spongy bone and lines the inner surfaces of the central canals
What are the three types of blood vessels associated with bones and what potion of the bone does each supply?
the nutrient artery and vein: supplies the diaphysis form; metaphyseal vessels: supply blood to the inner surface of each epiphyseal cartilage; periosteal vessels: provide blood to the superficial osteons of the shaft
Describe the function of the hormone calcitroil. What is its synthesis dependent on?
to promote calcium and phosphate ion absorption along the digestive tract; it is dependent on the kidneys
What are the four specialized cells found in bone tissue, and what is the function of each?
osteocytes: maintain the protein and mineral content of the surrounding matrix, participate in the repair of damaged bone; osteoblasts: produce a new bone matrix; osteoprogenitor cells: help with the reproduction of osteoblasts; osteoclasts: remove and recycle bone matrix
Describe the four steps of bone fracture repair.
Step 1: Immediately after the fracture, extensive bleeding occurs. Over a period of several hours, a large blood clot, or fracture hematoma, develops. Step 2: An internal callus forms as a network of spongy bone unites the inner edges, and an external callus of cartilage and bone stabilizes the outer edges. Step 3: The cartilage of the external callus has been replaced by bone, and struts of sponge bone now unite the broken ends. Fragments of dead bone and the areas of bone closest to the break have been removed and replaced. Step 4: A swelling initially marks the location of the fracture. Over time, this region will be remodeled, and little evidence of the fracture will remain.
Compare and contrast osteopenia and osteoporosis.
osteopenia: inadequate ossification, leading to thinner, weaker content; osteoporosis: a reduction in bone mass to a degree that compromises normal function
Why might a person with kidney failure exhibit symptoms similar to osteoporosis?
If the kidney does not retain the blood calcium levels and the osteoblasts and osteoplasts produce more calcium which is released through urination making the bones weak which is similar to osteoporosis
What are the divisions of the skeletal system and how many bones are in each?
the skull: 8cranial and 14 facial bones; bones associated with the skull: 6 auditory ossicles and the hyoid bone; the vertebral column: 24 vertebrae, the sacrum, and the coccyx; the thoracic cage: the sternum and 24 ribs
How many bones comprise the skull?
8 cranial bones and 14 facial bones
What are the 3 functions of the axial skeleton?
adjust the positions of the head, neck, and trunk; perform respiratory movements; stabilize or position parts of the appendicular skeleton, which supports the limbs
What are the 2 functions of the sinuses?
make a bone much lighter than it would otherwise be; the mucous membrane lining them produces mucus that moistens and cleans the air in and adjacent to the sinus
Describe the anatomy of the ethmoidal bone and discuss the relationship between that anatomy and olfactory reception?
it forms the anteromedial floor of the cranium, the roof of the nasal cavity, and part of the nasal septum and medial orbital wall; olfactory receptors are located in the epithelium that covers the inferior surfaces of the cribriform plate, which ensures the sense of smell
What are the 5 regions of the vertebral column?
cervical, thoracic, lumbar, sacral, coccygeal
Distinguish between lumbar, thoracic, and cervical vertebrae.
lumbar: inferior portion of back; massive, oval, flat faces; blunt, broad; short, no articular facets; supports the weight; thoracic: found in the chest; medium, heart shaped, flat faces; cervical: found in the neck, small oval, and curved faces
Describe the interaction between C1, C2, and the skull.
C1, the atlas, attaches directly to the skull and C2, the axis, connects to the spine
Describe the anatomy of the sacrum.
composed of 5 sacral vertebrae; used for protection of the reproductive, digestive, and urinary organs; has a broad posterior surface that provides an extensive area for the attachment of muscles, median sacral crest is a ridge formed by the fused spinous process of the sacral vertebrae - pg 238
How many ribs do humans have? Distinguish between true ribs, floating ribs, and false ribs.
24 ribs, or 12 pairs of ribs; true ribs: first 7 pairs; they reach the anterior body wall and are connected to the sternum by separate cartilaginous extensions; false ribs: ribs 8-12; they do not connect directly to the sternum; floating ribs: ribs 11 & 12; they do not connect to the sternum at all
Describe the anatomy of the sternum.
the manubrium is a broad triangular bone that articulates with the clavicles and the cartilage of the first pair of ribs; the body attaches to the inferior surface of the manubrium; the xiphoid process attaches to the inferior surface of the body and is the point of attachment for the diaphragm and rectus abdominus
Describe the relationship between the temporal bone and the ear.
the temporal bone protects and surrounds the sense organs in the inner ear
Describe the function of the fontanels during birth.
Fontanelles, which are fibrous connections between cranial bones, permit the skull to distort without damage during delivery, helping to ease the child through the birth canal
How many bones form the skull? How many are cranial bones? How many are facial?
22 bones; 8 are cranial bones and 14 are facial bones
List the cranial and facial bones.
cranial: occipital, frontal, sphenoid, ethmoid, paired parietal, and paired temporal; facial: maxillae (2), palatine bones (2), nasal bones (2), inferior nasal conchae (2), zygomatic bones (2), lacrimal bones (2), vomer, and mandible
List and describe the four major sutures of the skull.
lambdoid suture: arches across the posterior surface of the skull, separates the occipital bone from the two parietal bones; coronal suture: attaches the frontal bone to the parietal bones of either side; sagittal suture: extends from the lambdoid suture to the coronal suture; squamous suture: on each side of the skull forms the boundary between the temporal bone and the parietal bone of that side
Describe the etiology and symptoms of TMJ.
a highly mobile joint with a relatively loose connective tissue capsule; the mandible is pulled out of alignment, generally by a spasm in one of the jaw muscles
Describe three common abnormal distortions of the spinal curvatures.
kyphosis: the normal thoracic curvature becomes exaggerated posteriorly, producing a round back appearance; lordosis: "swayback" an anterior exaggeration of the lumbar region causing the abdomen and buttocks to protrude abnormally; scoliosis: the lateral curvature of the spine
What are the three functions of the turbulence created by the nasal conchae?
increase epithelial surface area, promote warming and slow down the inhalation of humidification in the air
Occipital condyle:
the site of the articulation between the skull and first vertebra; balances weight of the head over the neck
Foramen magnum:
connects the cranial cavity with the spinal cavity, which is enclosed by the vertebral column
Metopic suture:
generally runs down the center of the frontal squama, but usually disappears once the two frontal bones are fused together
Mastoid process:
an attachment site for muscles that rotate or extend the head
Styloid process:
near the base of the mastoid process, is attached to ligaments that support the hyoid bone and to the tendons of several muscles associated with the hyoid bone, the tongue, and the pharynx
External acoustic meatus:
on the lateral surface ends at the tympanis membrane
Internal acoustic meatus:
begins on the medial surface of the petrous part of the temporal bone, carries blood vessels and nerves to the inner ear and conveys the facial nerve to the stylomastiod foramen
Sella turcica:
a bony saddle shaped enclosure on the superior surface of the body
Ramus of the Mandible:
the ascending part that begins at the mandibular angle on either side consisting of the condylar process, coronoid process, and mandibular notch
Hyoid Bone:
supports the larynx and is an attachment site of muscles of the larynx, tongue, and pharynx
Which of the following lists contains only facial bones?
mandible, maxilla, nasal, zygomatic
The unpaired facial bones include the
vomer and mandible
The boundaries between skull bones are immovable joints called
The joint between the frontal and parietal bones is correctly called the ________ suture.
Blood vessels that drain blood from the head pass through the
jugular foramina
Cervical vertebrae can usually be distinguished from other vertebrae by the presence of
transverse foramina
The side walls of the vertebral foramen are formed by the
The part(s) of the vertebra that transfer(s) weight along the axis of the vertebral column is (are) the
Which eight bones make up the cranium?
Occipital bone, frontal bone, sphenoid, ethmoid, paired parietal bones and paired temporal bones
What seven bones constitute the orbital complex?
Sphenoid, frontal bone, ethmoid, lacrimal bone, maxilla, palatine bone, and zygomatic bone
What is the primary function of the vomer?
The vomer forms the anterior, inferior portion of the bony nasal septum that separates the right and left nasal cavities
Which bones contain the paranasal sinuses?
The frontal bone, sphenoid, ethmoid, the palatine bones, and the maxilla
What is the relationship between the temporal bone and the ear?
The petrous part of the temporal bone encloses the structures of the inner ear. The middle ear is located in the tympanic cavity within the petrous part. The external acoustic meatus ends at the tympanic membrane, which leads to the inner ear. Mastiod air cells within the mastoid process are connected to the tympanic cavity.
What is the relationship between the ethmoid and the nasal cavity?
The ethmoid forms the superior surface of the nasal cavity. The olfactory foramina within the cribriform plate of the ethmoid allow neurons associated with the sense of smell to extend into the nasal cavity
Describe how ribs function in breathing?
The ribs raise and lower t increase and decrease the volume of the chest cavity. They move similar to the handle of a bucket. When they rise, the chest activity expands and we breathe in. When the ribs are lowered to their original position, the volume of the chest cavity decreases and we breathe out.
Why is it important to keep your back straight when you lift a heavy object?
Keeping your back straight keeps the weight aligned along the axis of your vertebral column, where it can be transferred to your lower limbs. Bending your back would strain the muscles and ligaments of the back, increasing the risk of injury.
The atlas (C1) can be distinguished from the other vertebrae by
the presence of anterior and posterior vertebral arches; the lack of a body; the presence of superior facets and inferior articular facets
What purpose do the fontanelles serve during birth?
Fontanelles, which are fibrous connections between cranial bones, permit the skull to distort without damage during delivery, helping to ease the child through the birth canal
The secondary spinal curves
help position the body weight over the legs
When you rotate your head to look to one side,
the atlas rotates on the dens of the axis
Improper administration of CPR can force the _______ into the liver.
xiphoid process
Jane has an upper respiratory infection and begins to feel pain in her teeth. This is a good implication that the infection is located in the
maxillary sinuses
While working at an excavation, an archaeologist finds several small skull bones. She examines the frontal, parietal, and occipital bones and concludes that the skulls are those of children not yet 1 year old. How can she tell their ages from an examination of these bones?
The large bones of a child's cranium are not yet fused; they are connected by fontanelles, areas of fibrous tissue. By examining the bones, the archaeologist could readily see if sutures had formed. By knowing approximately how long it takes for the various fontanelles to close and by determining their sizes, she could estimate the age of the individual at death.
Mary is in her last month of pregnancy and is suffering from lower back pains. Since she is carrying excess weight in front of her, she wonders why her back hurts. What would you tell her?
Women in later stages of pregnancy develop lower back pain because of changes in the lumbar curvature of the spine. The increased mass of the pregnant uterus shifts the woman's center of gravity. To compensate, the lumbar curvature is exaggerated, and the lumbar region supports more of her body weight than normal.
Name the skeletal components of the pelvic girdle.
a pair of hipbones, sacrum, and coccyx
Which bones make up the arm and forearm?
the humerus, radius, and ulna
Name the components of the os coxae.
an ilium, an ischium, and a pubis
Why are injuries to the clavicle common?
because the clavicle is a relatively small and fragile bone
Name three functions of the clavicle and scapula.
position the shoulder joint; help move the upper limb; provide a base for muscle attachment
Describe the arrangement of the bones of the wrist.
the carpus, or wrist contains 8 carpal bones; these bones form two rows, four proximal carpal bones, and four distal carpal bones; the carpal bones articulate with one another at joints that permit sliding and twisting
List 6 differences between male and female pelves.
an enlarged pelvis outlet; less curvature of the sacrum and coccyx (in males they curve into the pelvic outlet); a wider, more circular pelvic inlet; a broad low pelvis; ilia that project farther laterally but not as far superiorly as in males; the pubic angle > 100°
Describe the structure of the acetabulum.
it is a concave socket that articulates with the head of the femur, a ridge of bone forms the lateral an superior margins with at 5cm diameter.
Distinguish between the false and true pelvis.
true (lesser) pelvis encloses the pelvic cavity. The superior limit of the true pelvis is a line that extends from either side of the base of the sacrum, along the arcuate line and pectineal line to the pubic symphysis.; false (greater) pelvis consists of the expanded, bladelike portions of each ilium superior to the pelvic brim
What is Runner's knee and what causes it?
it is developed from improper tracking of the patella so that it runs laterally to the normal track. It is caused by running on hard or slanted surfaces and inadequate arch support are often responsible.
Describe the distribution of body weight from the tibia to the foot.
when you stand normally, most of your weight is transmitted from the tibia, to the talus, to the calcaneus, and then to the ground
Which of the following is primarily responsible for stabilizing, positioning, and bracing the pectoral girdle?
In anatomical position, the ulna lies
medial to the radius
The point of the elbow is actually the ______ of the ulna.
The bones of the hand articulate distally with the
The epiphysis of the femur articulates with the pelvis at the
What is the name of the flexible that interconnects the radius and ulna (and the tibia and fibula)?
interosseus membrane
Name the components of each coxal bone.
ischium, ilium, and pubis
Which seven bones make up the ankle (tarsus)?
talus, calcaneus, cubois, navicular, and 3 cuneiform bones
The presence of tubercles on bones indicates the positions of
tendons and ligaments; muscle attachment
At the glenoid cavity, the scapula articulate with the proximal end of the
All of the following structural characteristics of the pelvic girdle adapt it to the role of bearing the weight of the body,
heavy bones, strong and stable articulating surfaces, limited range of movement at some of the joints within the pelvic girdle, the arrangement of ligaments surrounding the joints
The large foramen between the pubic and ischial rami is the
obturator foramen
Which of the following is an adaptation for childbearing?
inferior angle of 100° or more between the pubic bones, a relatively broad, low pelvis, less curvature of the sacrum and coccyx
The fibula
provides lateral stability to the ankle
The tarsal bone accepts weight and distributes it to the heel or toes is the
What is the difference in skeletal structure between the pelvic girdle and the pelvis?
The pelvic girdle consists of the coxal bones. The pelvis is a composite structure; it consists of the coxal bones of the appendicular skeleton and the sacrum and coccyx of the axial skeleton
Jack injures himself playing hockey, and the physician who examines him informs him that he has dislocated his pollex. What part of Jack's body did he injure?
his thumb
Why would a self-defense instructor advise a student to strike an assailant's clavicle?
The clavicles are small and fragile, so they are easy to break. Once this part of the pectoral girdle is broken, the assistant would no longer have efficient use of the arms
The pelvis
contains bones from both the axial and appendicular skeletons; is composed of the coxal bone, sacrum, and coccyx
Why is the tibia, but not the fibula, involved in the transfer of weight to the ankle and foot?
The slender fibula parallels the tibia of the leg and provides an important site for muscle attachment. It does not help in transferring weight to the ankle and foot because it is excluded from the knee joint.
In determining the age of a skeleton, all of the following pieces of information would be helpful
the number of cranial sutures, the size and roughness of the markings of the bones, the presence or absence of fontanelles, the presence or absence of epiphyseal cartilages
Why would a person suffering from osteoporosis be more likely to suffer a broken hip than a broken shoulder?
In osteoporosis, a decrease in the calcium content of the bones leads to bones that are weak and brittle. Because the hip must help support the body's weight, any weakening of the hip bones may result in their breaking under the weight of the body. The shoulder, by contrast, is not a load-bearing joint and is not subject to the same great stresses or strong muscle contractions as the hip joint. As a result, it is less likely to become broken.
While Fred, a fireman, is fighting a fire in a building, part of the ceiling collapses, and a beam strikes him on his left shoulder. He is rescued, but has a great deal of pain in his shoulder. He cannot move his arm properly, especially in the anterior direction. His clavicle is not broken, and his humerus is intact. What is the probable nature of Fred's injury?
Fred probably dislocated his shoulder, which is quite a common injury due to weak nature of the glenohumeral joint.
Archaeologists find the pelvis of a primitive human and are able to identify the sex, the relative age, and some physical characteristics of the individual. How is this possible from only the pelvis?
Several characteristics are important in determining an individual's sex from a pelvis; its general appearance, the shape of the pelvic inlet, the depth of the iliac fosa, the characteristics of the ilium, the angle inferior to the pubic symphysis, the position of the acetabulum, the shape of the obturator foramen, and the characteristics of the ischium. The individual's age can be estimated by the bone's size, degree of mineralization, and various markings. The individual's general appearance can be reconstructed from the markings where muscles attach to the bones, which can indicate the size and shape of the muscles and thus the individual's general body contours