Bones Chapter 7
How are bones classified?
according to their shapes- long, short, flat, irregular, or sesamoid.
In the skeletal system, compact bone is
located where bones are most heavily stressed
Diaphysis
shaft of a long bone
Describe the major steps in the repair of a fracture.
1) the formation of hematoma at the break 2) the formation of a fibrocartilaginous callus 3) the formation of a bony callus 4) remodeling and addition of compact bone.
What is a hematoma?
A pool of mostly clotted blood that forms in an organ, tissue, or body space. A hematoma is usually caused by a broken blood vessel that was damaged by surgery or an injury. It can occur anywhere in the body, including the brain.
Explain how an endochondral bone develops.
Although bone initially forms during fetal development, it undergoes secondary ossification after birth and is remodeled throughout life.
Explain regulation of the concentration of blood calcium.
Blood calcium levels are regulated by parathyroid hormone (PTH), which is produced by the parathyroid glands. PTH is released in response to low blood calcium levels. It increases calcium levels by targeting the skeleton, the kidneys, and the intestine.
How are living tissues found in bone
Bone is made up of compact tissue (the hard, outer layer) and cancellous tissue (the spongy, inner layer that contains red marrow). Bone tissue is maintained by bone-forming cells called osteoblasts and cells that break down bone called osteoclasts.
What are the general functions of bones?
Bone provides shape and support for the body, as well as protection for some organs. Bone also serves as a storage site for minerals and provides marrow for the development and storage of blood cells.
List the substances normally stored in bone tissue.
Calcium, phosphorus, magnesium, sodium, potassium, and carbonate ions are normally stored in bone tissue.
Medullary Cavity
Compact Bone in Diaphysis of a long bone forms a semi rigid tube, which is a hollow chamber
Describe the microscopic structure of compact bone.
Compact bone consists of closely packed osteons or haversian systems. The osteon consists of a central canal called the osteonic (haversian) canal, which is surrounded by concentric rings (lamellae) of matrix.
Locate and name each of the bones of the cranium
Each bone in the cranium (skull) is called frontal, parietal, occipital, temporal, sphenoid, ethmoid.
Locate and name each of the facial bones.
Each bone of the facial are called Maxilla, Zygomatic, Palatine, Inferior Nasal Concha, Mandible, Lacrimal, Nasal, Vomer.
Epiphysis
End of a long bone
How are male and female pelves different?
Female pelvis is larger and wider than the male pelvis and has a rounder pelvic inlet. Male iliac crests are higher than females, causing their false pelvis to look taller and narrower. The male sacrum is longer, narrower, straighter, and has a pronounced sacral promontory relative to the female sacrum.
Explain how the bones of the upper limb articulate.
Humerus has a rounded head on its upper end that fits the glenoid cavity of the scapula. Greater tubercles and lesser tubercles provide attachments for muscles that move the upper limb and shoulder. At the lower end of the humerus are two smooth condyles that articulate with the radius on in the lateral side and the ulna on the medial side. Above the condyles on either sides are epicondyles, which provide attachments for muscles and ligaments of the elbow.
Describe the development of intramembranous bone.
Intramembranous ossification involves the replacement of sheet-like connective tissue membranes with bony tissue. They include certain flat bones of the skull and some of the irregular bones.
Describe how the foot is adapted to support the body.
Its phalanges and metatarsal bones are large and strong. Together, the tarsal and metatarsal bones of the foot form a longitudinal arch, which absorbs shock in walking; a transverse arch, across the metatarsals, also helps distribute weight. The heel bone helps support the longitudinal foot arch.
Flat Bone
Platelike structure w/ broad surfaces (ex: ribs, scapulae & some bones of the skull)
Osteoblasts
Progenitor cells enlarge & further differentiate into bone-forming cells
Distinguish between the functions of red marrow and yellow marrow.
Red bone marrow contains blood stem cells that can become red blood cells, white blood cells, or platelets. Yellow bone marrow is made mostly of fat and contains stem cells that can become cartilage, fat, or bone cells.
Marrow
Soft Connective Tissue
Name the 3 parts of the sternum
The 3 parts of the sternum are the upper Manubrium, a middle body, and a lower xiphoid process that projects downward.
Distinguish between the false pelvis and the true pelvis.
The false pelvis is related to the abdominal cavity anteriorly and superiorly and contains most of the small bowel, parts of the colon, and the common iliac vessels. The true pelvis contains some small bowel, the rectum, the urinary bladder, and the reproductive organs.
name the bones that fuse to form the hip bone.
The hip bone is formed by the fusion of three bones, the ilium, the ischium, and the pubis.
Locate and name each of the bones of the upper limb.
The humerus, radius, ulna, carpals, metacarpals, phalanges
How do compact bone and spongy bone differ in structure?
The main difference between compact and spongy bone is that compact bone is the hard outer layers of the bone whereas spongy is the more porous, inner layers of the bone.
List the five major parts of a long bone.
The major parts of a long bone include epiphysis, articular cartilage, diaphysis, periosteum, medullary cavity, endosteum, and marrow.
Locate and name each bone that forms the pelvis.
The pelvic girdle, also known as the hip bone, is composed of three fused bones: the ilium, ischium and the pubic bone.
Which bones compose the thoracic cage?
The thoracic cage compose of the ribs, the thoracic vertebra, sternum, and costal cartilages.
Describe the structure of the vertebral column.
The vertebral column extends from the skull to the pelvis and forms the vertical axis of the skeleton. It is composed of many body parts (vertebrae) that are separated by masses of fibrocartilage called intervertebral disks.
Locate and name each of the bones of the lower limb.
These are the thigh, located between the hip and knee joints; the leg, located between the knee and ankle joints; and distal to the ankle, the foot. There are 30 bones in each lower limb. These are the femur, patella, tibia, fibula, seven tarsal bones, five metatarsal bones, and 14 phalanges.
Endosteum
Thin layers of cells
Explain how the bones of the lower limb articulate.
Three areas of articulation form the ankle joint: The superomedial surface of the talus bone articulates with the medial malleolus of the tibia, the top of the talus articulates with the distal end of the tibia, and the lateral side of the talus articulates with the lateral malleolus of the fibula.
What are the differences among true, false, and floating ribs?
True ribs are the first 7 rib pairs, they join the sternum directly by their costal cartilages. False ribs are the remaining 5 pairs, because their cartilages don't reach the sternum directly . The last 2 or 3 ribs are called the floating ribs, they have no cartilaginous attachments to the sternum.
How is a fracture classified?
When a fracture happens, it's classified as either open or closed. Open fracture: The bone pokes through the skin and can be seen, or a deep wound exposes the bone through the skin. Closed fracture (also called simple fracture). The bone is broken, but the skin is intact.
What is the function of the pectoral girdle?
Your pectoral girdles are responsible for providing structural support to your shoulder region on the left and right side of your body. They also allow for a large range of motion, connecting muscles necessary for shoulder and arm movement.
osteogenesis
formation of bone
The arches of the foot
metatarsal bones
Immature, active bone cells that produce new bone material are
osteoblasts
bone cells whose primary function is to break down bone tissue to remodel the bone or release stored calcium are named osteoclasts
osteoclasts
The microscopic bony chambers that house mature bone cells are called
osteons
Which of the following is part of the structure of compact bone but is not found in spongy bone
osteons
The presence of cartilage at the epiphyseal plate indicates that
the bone can still lengthen
