1) Which bone (yellow) is centrally located and joins with most of the other bones of the skull?
-Sphenoid bone is located at the center and connects with most of the other bones in the skull.
2) What are the two mechanisms by which the bones of the body are formed and which bones are formed by each mechanism?
A) Intramembraneous
-MECHANISM: bone forms directly from fibrous membranes within the mesenchyme
-EXAMPLES: flat bones of the skull, mandible, and clavicle
B) Endochondral
-MECHANISM: bone forms within hyaline cartilage that develop from the mesenchyme
-EXAMPLES: long bones such as arms (humerus, radius, ulna), legs (femur, tibia, fibula), fingers (metacarpals, phalanges), and toes (metatarsals, phalanges)
3) What are the synovial joints being described in the video?
A) Plane or gliding joints
-DESCRIPTION: consist of two opposed flat surfaces that glide over each other.
-EXAMPLES: articular facets between vertebrae
B) Saddle joints
-DESCRIPTION: consist of two saddle-shaped articulating surface-oriented at right angles to each other
-movement in these joints can occur in two planes.
-EXAMPLES: joint between the metacarpal bone and the carpal bone (trapezium) of the thumb
C) Hinge joints
-DESCRIPTION: permit movement in one plane only
-consist of a convex cylinder of one bone applied to a corresponding concavity of the other bone
-EXAMPLES: elbow and knee joints
D) Pivot joints
DESCRIPTION: rotation around a single axis
-consists of a cylindrical bony process that rotates within a ring composed partly of bone and partly of ligament
-EXAMPLES: rotation of axis and atlas when shaking the head “no”
-proximal ends of the ulna and radius
E) Ball-and-socket joints
-DESCRIPTION: consist of a ball (head) at the end of one bone and a socket in an adjacent bone
-allows a wide range of movement in almost any direction
-EXAMPLES: shoulder and hip joints
F) Ellipsoid or condyloid joints
-DESCRIPTION: elongated ball-and-socket joints
-range of movement nearly to that of a hinge motion, but in two planes.
-EXAMPLES: joint between the occipital condyles of the skull and the atlas of the vertebral column
-Joints between the metacarpal bones and phalanges.
4) Which type of synovial joint allows for the widest ranges of motion?
-Ball-and-socket joints allow the widest ranges of motion since they are capable of movement from any direction.
REFERENCES:
Brain Kart. (n.d.). Essentials of human anatomy and physiology: Skeletal system: Joints. https://www.brainkart.com/article/Joints_21786/