Bio150Lab Review Quiz #4

• those bones that lie around the body's center of gravity
• The axial skeleton can be divided into three parts, the skull, the vertebral column, and the bony thorax

bones of the limbs or appendages

cover the bone ends at movable joints

found connecting the ribs to the sternum (breastbone)

largely construct the larynx (voice box)

reinforce other passageways of the respiratory system

support the external nose

separate and cushion bones of the spine (vertebrae)

a dense connective tissue covering that surrounds cartilage

the most abundant cartilage type in the body; provides firm support with some pliability

much more flexible than hyaline cartilage, and it tolerates repeated bending better

Only the cartilages of the external ear and the epiglottis (which flops over and covers the larynx when we swallow) are elastic cartilage.

consists of rows of chondrocytes alternating with rows of thick collagen fibers

looks smooth and homogeneous

is composed of small trabeculae (bars) of bone and lots of open space

such as the femur and phalanges (bones of the fingers) are much more longer then they are wide, generally consisting of a shaft with heads at either end.

Long bones are composed predominantly of compact bone

are typically cube shaped, and they contain more spongy bone than compact bone

e.g. the tarsals and carpals

are generally thin, with two waferlike layers of compact bone sandwiching a layer of spongy bone between them

many flat bones are curved for example the bones of the skull

bones that do not fall into one of the preceding categories

e.g. the vertebrae are irregular bones

are special types of short bones formed in tendons

e.g. the patellas (kneecaps) are sesamoid bones

are tiny bones between cranial bones

scarred areas with and array of bumps, holes, and ridges; reveal where bones form joints with other bones, where muscles, tendons, and ligaments were attached and where blood vessels and nerves passed

bone markings fall into two categories: projections and depressions

processes that grow out from the bone and serve as sites of muscle attachment or help form joints

indentations or openings in the bone that often serve as conduits for nerves and blood vessels

or shaft, observe its smooth surface, which is composed of compact bone.

fibrous membrane covering

many fibers of the periosteum penetrate into the bone

bone forming cells

bone-destroying cells

both cells are found on the inner or osteogenic, layer of the periosteum

the end of the long bone, composed of a thin layer of compact bone that encloses spongy bone

covers the epiphyseal surface in place of the periosteum. b/c it is composed of glassy hyaline cartilage, it provides a smooth surface to prevent friction at joint surfaces.

a thin area of hyaline cartilage that provides for longitudinal growth of the bone during youth.

once the long bone has stopped growing, these areas are replaced with bone and appear as thin, barely discernible remnants

lining the shaft, also covers the trabeculae of spongy bone and lines the canals of compact bone.

spongy bone has a spiky, open-work appearance, resulting from the arrangement of the trabeculae that compose it, whereas compact bone appears to be dense and homogeneous.

runs parallel to the long axis of the bone and carries blood vessels, nerves, and lymph vessels through the bony matrix.

mature bone cells

chambers

concentric circles around the central canal

central canal and all the concentric lamellae surrounding it

The canaliculi allow each cell to take what it needs for nourishment and to pass along the excess to the next osteocyte.

• tiny canals radiating outward from a central canal to the lacunae of the first lamella and then from lamella to lamella.
• The canaliculi allow each cell to take what it needs for nourishment and to pass along the excess to the next osteocyte.

these canals run into compact bone and marrow cavity from the periosteum, at right angles to the shaft

• uses hyaline cartilage “bones” as patterns for bone formation. The major events of this process, which begins in the (primary ossification) center of the shaft of a developing long bone are:
• The fibrous membrane covering the hyaline cartilage model is vascularized and converted to a periosteum
• Osteoblasts at the inner surface of the periosteum secrete bone matrix around the hyaline cartilage model, forming a bone collar
• cartilage in the shaft center calcifies and then hollows out, forming an internal cavity

(blood vessels, nerves, red marrow elements, osteoblasts, and osteoclasts) invades the cavity, which becomes the medullary cavity.

enclose and protect the fragile brain tissue

present the eyes in an anterior position and form the base for the facial muscles, which make it possible for us to present our feelings to the world.

forming the superior, lateral, and posterior walls of the skull

• forming the skull bottom
• The cranial floor has three distinct concavities, the anterior, middle, and posterior cranial fossae

• eight bones construct the cranium, with the exception of two paired bones (the parietals and the temporals), all are single bones
• The eight bones are Frontal bone, Occipital bone, Sphenoid bone, Ethmoid bone, Lacrimal bone, Palatine bone, Zygomatic bone, Nasal Bone

anterior portion of cranium; forms the forehead, superior part of the orbit, and floor of anterior cranial fossa.

opening above each orbit allowing blood vessels and nerves to pass

smooth area between the eyes

posterolateral to the frontal bone, forming sides of cranium

midline articulation point of the two parietal bones

point of articulation of parietals with frontal bone

inferior to parietal bone on lateral skull. The temporals can be divided into four major parts: the squamous region abuts the parietals; the tympanic region surrounds the external ear opening; the mastoid region is the area posterior to the ear; and the petrous region forms the lateral portion of the skull base.

point of articulation of the temporal bone with the parietal bone

a bridgelike projection joining the zygomatic bone (cheekbone) anteriorly. together these two bones form the zygomatic arch.

rounded depression on the inferior surface of the zygomatic process (anterior to the ear); forms the socket for the mandibular condyle, the point where the mandible (lower jaw) joins the cranium.

canal leading to eardrum and middle ear.

needlelike projection inferior to external acoustic meatus; attachment point for muscles and ligaments of the neck. This process is often broken off demonstration skulls

rough projection inferior and posterior to external acoustic meatus; attachment site for muscles.

opening medial to the styloid process through which the internal jugular vein and cranial nerves IX, X, and XI pass.

opening medial to the styloid process through with the internal carotid artery passes into the cranial cavity.

opening on posterior aspect (petrous region) of temporal bone allowing passage of cranial nerves VII and VIII.

a jagged opening between the petrous temporal bone and the sphenoid providing passage for a number of small nerves and for the internal carotid artery to enter the middle cranial fossa (after it passes through part of the temporal bone).

most posterior bone of cranium-forms floor and back wall. Joins sphenoid bone anteriorly via its narrow basioccipital region

the vertebrae are separated by pads of fibrocartilage, that cushion the vertebrae and absorb shocks

the nucleus pulposus herniates through the annulus portion and typically compresses adjacent nerves.