Lab 9 & 10 Flashcards
___ named bones
206
Skeleton is divided into:
Axial and Appendicular
Axial skeleton is composed of ____ bones
80
Appendicular skeleton is composed of ____ bones
126
The axial skeleton consists of bones that form the ____ ____ of the body
Long axis
Skull, vertebral column and thoracic cage:
Axial skeleton
The ______ skeleton consists of bones from the upper and lower limbs, plus the bones forming the girdles that connect the limbs to the axial skeleton
Appendicular
Five main types of bones:
Long, short, flat, irregular, and sesamoid
Bones that are longer than they are wide
Long bones
Most of the bones of the limbs are ____ bones
Long
Long bones are _____ for strength
Curved
Compact bone occurs at the surface of long bones, particularly in the ______
Diaphysis
The dilated extremities or epiphyses consist of _____ bone covered by a thin layer of compact bone
Spongy
Cube shaped bones (wrist/ankle or carpal/tarsal)
Short bones
Thin, flattened, usually a bit curved (sternum, scapular, ribs, skull)
Flat bones
Complicated shapes, don’t fit other classes (vertebrae, hip bones)
Irregular bones
Shaped like sesame seed, special short bone that forms patella (kneecap)
Sesamoid bones
The external surfaces of bones are rarely smooth, but instead have characteristic:
Surface markings
Composed of bones which form the long axis of the skeleton: the skull, auditory ossicles (middle ear bones - malleus, incus, stapes), hyoid bone, the vertebral column, the sternum and the ribs
Axial skeleton
Areas of fibrous connective tissue called _____, still exist between the cranial bones
Known as “soft spots”
Fontanels
The fontanels provide some flexibility to the fetal skull. Which allows:
Rapid growth
Skull to compress during birth
Ossification is usually complete by ____ years of age and the fontanels become sutures
Two
The adult skull is formed by cranial and facial bones, ____ in total
22
Enclose and protect the brain and are a site of attachment of head and neck muscles:
Cranial bones
Are immovable joints:
Sutures
Four major sutures:
Coronal, sagittal, squamous, and lambdoid sutures
Only movable bone in the skull
Mandible
Which structure passes through the foramen magnum?
Spinal cord
The occipital condyles rest upon which bone?
Atlas (specifically superior fascets)
How many bones form the face? Name them
14 bones: 2 maxillae, 2 zygomatic, 2 nasal, 2 lacrimal, 2 palatine, 2 inferior nasal conchae, 1 mandible, 1 vomier
How many bones form the eye orbit? Name them
7 bones: frontal, sphenoid, zygomatic, maxilla, palatine, lacrimal, ethmoid
An isolated U-shaped bone, lies in the anterior part of the neck just below the mandible
Hyoid bone
The hyoid bone functions as an attachment point for the muscles of:
Tongue and larynx
The hyoid bone is the only bone of the body that does not directly _____ with any other bone
Articulate
The ______ ______ constitutes the longitudinal axis of the body
Vertebral column
The vertebral column functions as a _____ and ______ ___ that extend from the skull to the pelvic area
Strong; flexible rod
Vertebrae typically consist of a ______ _____ shaped body, a ______ ______ which contains the spinal cord and several processes
Thick disc-shaped body, a vertebral foramen
The vertebral column _____ the head and serves as an ______ point for the ribs and pelvic girdle, and for the muscles of the neck and back
Supports; attachment
Four curvatures give the vertebral column its:
S or sinusoid shape
The cervical and lumbar curves are:
Convex (bulging out)
The thoracic and sacral curves are:
Concave (cupping in)
These curvatures of the vertebral column: (4 things)
Increase strength
Maintain balance
Absorb shock when moving
Protect vertebrae from fracture
The cervical region of the vertebral column consists of _ vertebrae
7 (C1 to C7)
The lightest and smallest in the vertebral column
Cervical vertebrae
Cervical vertebrae possess ______ _____ that contain a ______ ______, for the passage of the vertebral artery and vein and the associated nerves.
Transverse processes; transverse foramen
The first two cervical vertebrae the ____ and ____, differ in structure from the other five “typical” cervical vertebrae
Atlas; axis
The atlas (C1) is essentially a bony ring which allow you to nod your head “yes” and supports the ______
Head
The axis (C2) has a large tooth-like process, the dens or odontoid process, which arises from the body of the vertebra and fits up into the anterior part of the atlas. As the head is turned from side to side, the atlas moves about the axis using the odontoid process as a pivot point. This the joint that allows you to:
Shake your head “no”
Except C1, C2, and C7, the spinous process is:
Bifid (divided by a deep cleft or notch into two parts)
Notched at the tip:
Bifid
The thoracic region of the vertebral column consists of ___ vertebrae
12
Heart-shaped body, a circular vertebral foramen, a long spinous process that points inferiorly to the presence of facets (and/or demifacets) for articulation with the ribs
“Typical” thoracic vertebra
The bones of the skeleton are attached to one another at joints or
Articulations
As the bones of the skeleton are rigid, movement can occur only at the
Joints
The joints of the bone body maybe classified in 2 ways - according to their:
Function and structure
The functional classification of joints is based on the amount of ______ that can occur at the joint.
Movement
There are three basic types of joints based on functional activities:
Synarthroses
Amphiarthroses
Diarthoroses
Synarthroses
Immovable joints
Amphiarthroses
Slightly moveable joints
Diarthoroses
Freely movable joints
The structural classification of joints relies on the type of ______ ______ which binds articulating surfaces together and on the presence or absence of a joint cavity.
Connective tissue
There are three structural categories of joints:
Fibrous joints
Cartilaginous joints
Synovial joints
In ______ _____ the articulating bones are firmly bound together by dense fibrous connective tissue.
Fibrous joints
Fibrous joints, the joint cavity is not present. They are are very strong and permit:
Little or no movement
Fibrous joints have two major types of joints in the structural division are:
Sutures & Syndesmoses
Are articulating bones that are held very close together by dense connective tissue. Functionally classified as synarthrosis or immovable joints. Example: joint found between the cranial and facial bones of the skull.
Sutures
Are the articulating bones that are united by a band of dense connective tissue. The amount of movement at this type of joint depends upon the length of the connecting fiber.
Example: joint found at the distal articulation between the tibia and fibula is classified as synarthrosis, or immovable true movement is prevented: best described as give
Syndesmoses
In these joints the articulating bones are bound to each other by cartilage. These joints lack a joint cavity and permit little or no movement.
Cartilaginous
Cartilaginous have two major types of joints in the structural division are:
Synchondroses
Symphyses
Articulating bones are connected by hyaline cartilage. Functionally classified in the adult as synarthrosis, or immovable joints. Examples: joint formed by the coastal cartilage is of rib number one and the manubrium of the sternum; epiphyseal plates in the long bones of children.
Synchondroses
Articulating bones are connected by fibrocartilage. Functionally classified as for amphiarthroses, Or slightly moveable joints. Examples: the intervertebral discs between the bodies of the vertebrae: pubic symphysis
Symphyses
Most joints in the body. The movement is limited only by ligaments, muscles, tendons, or adjoining bones. Are characterized as diarthrosis, or freely moveable joints.
Synovial Joints
The articulating bones are separated by a fluid filled joint cavity. Articular cartilage (hyaline) covers the surface of the articulating bones. The joint cavity is enclosed by an articular capsule, consisting of the outer layer, the fibrous capsule, and an inner layer, formed by the synovial membrane.
The synovial membrane secretes synovial fluid, which fills the synovial cavity, lubricates the joint, and provides nourishment for the articular cartilage.
Synovial joints are reinforced and strengthened by band like ligaments composed of dense regular connective tissue.
Distinguishing features of a synovial joint.
Synovial joints can be divided into six categories according to the shape of the articulating surfaces and the type of movement allowed.
(i) Plane (gliding) joints
(ii) hinge joints
(iii) pivot joints
(iv) condyloid (ellipsoid) joints
(v) saddle joints
(vi) ball and socket joints
articulating surfaces are essentially flat. Movement does not occur around an access non-axial: only allows slight movement. Examples: the joints between the carpal bones of the wrist and between the tarsal bones of the ankle; sternocostal joint between the sternum and the ribs number 2 to 7; vertebrocostal joint between the vertebrae in the ribs snow already said that there are no: intervertebral joint between the articular processes of the vertebrae; joint between tarsals and metatarsals; joint between carpals and metacarpals of digits numbers 2 to 5; joint between the lateral end of the clavicle and the acromion of scapula.
(i) Plane (gliding) joints
A convex surface of one bone fits into concave surface of another bone. Movement occurs around a single access monoaxial; permits flexion and extension. Examples: elbow joint; joint between the phalanges; ankle joint; knee joint modified hinge
(ii) hinge joints
Around its surface of one bone fits into a ring like portion of another bone. Movement occurs around a single Access Main axle; permits rotation. Examples: joint between the atlas and axis; joint between the head of the radius and the ulna
(iii) pivot joints
An oval convex surface of one bone fits into an oval concave surface of another bone. Movement occurs around two axes biaxial; permits all angular motions: flexion and extension, abduction and adduction, and circumduction. Oh and rotation. Example: joint between the carpal and metacarpal bone of the thumb.
(iv) condyloid (ellipsoid) joints
each articular surface has both convex and concave areas; the surface of one bone fits as a “rider” into the saddle of the other bone. Movement occurs around 2 axes (biaxial); permits all angular motions: flexion and extension, abduction and adduction, circumduction and rotation. Example: joint between the carpal and meta carpal bone of the thumb
(v) saddle joints
A ball like surface of one bone fits into a cup like depression of another bone. Movement occurs in all axes and plains multi axial or triaxial; permits all angular and rotational motions: Flexi on an extension, abduction and adduction, circumduction and rotation. Examples: shoulder joint; hip joint.
(vi) ball and socket joints
Movements that occur at synovial joints are given specific names with reference to:
Anatomical position
The movement of a limb or other body part away from the medial line of the body caused by the contraction of an abductor muscle
Abduction
The movement of a limb or other body part toward the medial line of the body caused by the contraction of an abductor muscle
Adduction
A bending movement that decreases the angle between articulating bones caused by the contraction of a flexor muscle. Two special terms are applied to ________ of the foot at the ankle joint.
Flexion
The toes pointed upward as when you stand on your heels
Dorsiflexion
The toes pointing downwards as when you stand on your tiptoes
Plantar flexion
A bending movement that increases the angle between articulating bones; straightening or extending a limb caused by the contraction of an extensor muscle
Extension
The continuation of extension beyond anatomical position
Hyper extension
