All Human Anatomy and Physiology Resources
Example Question #1 : Help With General Bone And Joint Structures
What type of bone cells secrete osteoid and synthesize bone?
Osteoblasts are differentiated non-dividing cells that secrete osteoid, an organic matrix material, that becomes mineralized forming bone. These are the cells primarily responsible for building bone.
Osteocytes are osteoblasts that become trapped in lacunae by bony matrix. These cells still maintain the bone environment, but do not actively build or modify bone a significant amount.
Osteoclasts resorb bone by breaking down the crystalline matrix.
Deposition of the calcium phosphate salt hydroxyapatite leads to mineralization of the bony matrix.
Example Question #2 : Help With General Bone And Joint Structures
Which of the following is NOT an example of a synarthrosis?
A synarthrosis is a type of joint that permits little or no movement. Syndesmoses, synostoses, and symphyses are all examples of synarthroses. Syndesmoses are joined by an interosseous ligament. Joints between carpals and tarsals are mostly syndesmoses. Synostoses is a joint formed from the fusion of two bones, generally in an atypical fashion. Symphyses can be synarthroses or amphiarthorses and are characterized by a fibrocartilage band between bones, such as in the pubic symphysis.
A diarthrosis, also known as a synovial joint, is the most common joint type in humans and allows free bone movement. The knee and elbow are examples of a diarthroses or synovial joints.
Example Question #3 : Help With General Bone And Joint Structures
Which of the following cannot be used to describe a joint?
The joints, or articulations, of the body can be classified according to several different criteria. They can be named for their structure, type of motion, or range of motion.
Synovial joints are determined by the joint structure. All synovial joints are housed within a joint capsule and contain synovial fluid. Joints between long bones are almost always synovial joints.
Syndesmoses are defined by their range of motion, and have very small, if any, motility. Syndesmoses are joined by interosseous ligaments, such as those between the carpals of the wrist.
Saddle joints are defined the type of motion allowed at the joint. Saddle joints are biaxial, allowing flexion, extension, adduction, and abduction, but no axial rotation. The pollical (thumb) joint is a saddle joint. While a "swinging joint" would seem to indicate a joint defined by its type of motion, no such joint exists in anatomical terms.
Example Question #4 : Help With General Bone And Joint Structures
What is the name of the concentric rings formed by osteoblasts in bone tissue?
Osteoblasts will lay down bone matrix around previously formed bone tissue. This forms concentric rings of bone tissue referred to as lamellae.
Lacunae are small gaps in the hydroxyapatite matrix that house the osteocytes. Trabeculae are thin bony structures that span and branch within the region of spongy bone. Canaliculi are small channels between lacunae that allow for cellular nourishment and communication. The epiphyses are the ends of the bone (as opposed to the diaphysis, or bone shaft).
Example Question #5 : Help With General Bone And Joint Structures
What is the medullary cavity?
Dense outer layer of bone
The marrow cavity
Shaft of a long bone
The end of a long bone
The marrow cavity
The medullary cavity is the bone marrow cavity contains red and/or yellow bone marrow; red bone marrow is the site of hematopoiesis. The end of a long bone is known as the epiphysis. Compact bone (cortical bone) is the dense outer layer of bone. The diaphysis is the shaft of a long bone.
Example Question #6 : Help With General Bone And Joint Structures
In long bones, which of the following areas has the greatest metabolic activity during growth?
Metaphysis: has the greatest metabolic activity, and contains the epiphyseal plate, which is replaced by the epiphyseal line
Diaphysis: mechanical support, site of bone marrow and muscle attachments
Apophysis: functions as a site for attachments of ligaments and tendons
Epiphysis: at the end of long bones
Periosteum: covers the diaphysis and parts of metaphysis.