1.
Which is a function of the skeletal system?
Correct Answer
E. All of these
Explanation
The skeletal system serves multiple functions. It provides support to the body, allowing us to maintain an upright posture and protecting our vital organs. It also functions as a hematopoietic site, where red and white blood cells are produced. Additionally, the bones of the skeletal system act as levers, enabling movement and providing attachment points for muscles. Lastly, the skeletal system serves as a storage site for minerals such as calcium and phosphorus. Therefore, all of the given options are correct functions of the skeletal system.
2.
A bone with approximately the same width, length and height is most likely:
Correct Answer
B. A short bone
Explanation
A bone with approximately the same width, length, and height is most likely a short bone. Short bones are typically cube-shaped or have a similar width, length, and height. These bones provide support and stability to the body and are found in areas such as the wrists and ankles. They are not as long as long bones, which are found in the arms and legs, and they are not flat like flat bones, such as the ribs or scapula. Additionally, they are not irregularly shaped like irregular bones, such as the vertebrae. Therefore, a bone with these dimensions is most likely a short bone.
3.
The shaft of a long bone is properly called the:
Correct Answer
C. DiapHysis
Explanation
The shaft of a long bone is properly called the diaphysis. The diaphysis is the long, cylindrical middle portion of a long bone, located between the two ends called epiphyses. It is mainly composed of compact bone, which provides strength and support to the bone. The diaphysis also contains a hollow cavity called the medullary cavity, which is filled with bone marrow. The periosteum is the tough outer covering of the bone, while the epiphysis refers to the rounded ends of the bone.
4.
Sites of hematopoiesis include all but:
Correct Answer
D. Medullary cavities in bones of a healthy adult
Explanation
Hematopoiesis is the process of formation and development of blood cells. It primarily occurs in the red marrow cavities of spongy bone and the dipole of flat bones. In infants, hematopoiesis also takes place in the medullary cavities of bones. However, in a healthy adult, hematopoiesis is limited to the red marrow cavities of spongy bone and does not occur in the medullary cavities. Therefore, the correct answer is "medullary cavities in bones of a healthy adult."
5.
An osteon has:
Correct Answer
E. All of these
Explanation
An osteon is a structural unit of compact bone. It consists of concentric lamellae, which are layers of bone tissue that surround a central canal. The central canal carries blood vessels, allowing for the transportation of nutrients and oxygen to the bone cells. Osteocytes, which are mature bone cells, are located in small spaces called lacunae within the lamellae. Canaliculi are tiny channels that connect the lacunae to the central canal, allowing for the exchange of nutrients and waste products between osteocytes and blood vessels. Therefore, all of these structures are present in an osteon.
6.
The organic portion of martrix is important in providing all but
Correct Answer
B. Hardness
Explanation
The organic portion of the matrix is important in providing tensile strength, ability to resist stretch, and flexibility. However, it does not play a significant role in determining hardness. Hardness is primarily influenced by the inorganic components of the matrix, such as minerals and crystals.
7.
The flat bones of the skull develop from
Correct Answer
C. Fibrous connective tissue
Explanation
The flat bones of the skull develop from fibrous connective tissue. During fetal development, the skull bones start as fibrous connective tissue membranes called fontanelles. These fontanelles gradually ossify and transform into the flat bones of the skull. Fibrous connective tissue provides flexibility and allows for the growth and shaping of the skull bones as the baby's brain grows. As ossification occurs, the fibrous connective tissue is replaced by compact bone, resulting in the formation of the flat bones of the skull.
8.
The remodeling of bone is a function of which cells?
Correct Answer
B. Osteoblasts and osteoclasts
Explanation
The remodeling of bone refers to the continuous process of breaking down old bone tissue and replacing it with new bone tissue. This process is carried out by two types of cells: osteoblasts and osteoclasts. Osteoblasts are responsible for the formation of new bone tissue, while osteoclasts are responsible for the breakdown and resorption of old bone tissue. Together, these cells work to maintain the balance and integrity of the skeletal system.
9.
Bone remodeling in adults is regulated and directed mainly by:
Correct Answer
D. Mechanical stress & PTH
Explanation
Bone remodeling in adults is regulated and directed mainly by mechanical stress and parathyroid hormone (PTH). Mechanical stress refers to the physical forces applied to the bones during activities such as weight-bearing exercises. These forces stimulate bone cells to remodel and strengthen the bone tissue. PTH, on the other hand, is a hormone produced by the parathyroid glands that plays a crucial role in maintaining calcium balance in the body. It stimulates bone resorption, which is the process of breaking down old bone tissue, and promotes the release of calcium into the bloodstream. Together, mechanical stress and PTH ensure the continuous renewal and adaptation of bone tissue to meet the body's needs.
10.
Where within the epiphyseal plate are the dividing cartilage cells located?
Correct Answer
C. Farthest from the shaft
Explanation
The dividing cartilage cells within the epiphyseal plate are located farthest from the shaft. This is because the epiphyseal plate is responsible for longitudinal bone growth, and the dividing cartilage cells are actively multiplying to lengthen the bone. As new cells are produced, they push the older cells away from the shaft, causing them to move towards the ends of the bone, which are farthest from the shaft.
11.
Wolff's law is concerned with:
Correct Answer
B. The thickness and shape of a bone being determined by mechanical and gravitational stresses placed on it
Explanation
Wolff's law states that the structure and shape of a bone are influenced by the mechanical and gravitational forces acting upon it. This means that bones will adapt and remodel themselves in response to the stresses placed upon them. For example, if a bone is subjected to increased mechanical loads, it will become thicker and stronger to withstand the forces. Similarly, if the bone is not exposed to sufficient stress, it may become weaker and more prone to fractures. Therefore, Wolff's law is concerned with how the thickness and shape of bones are determined by mechanical and gravitational stresses.
12.
Formation of the bony callus in fracture repair is followed by:
Correct Answer
C. Bone remodeling to convert woven bone to compact bone
Explanation
The correct answer is bone remodeling to convert woven bone to compact bone. After the formation of the bony callus, which is a bridge of new bone that stabilizes the fracture, the next step in fracture repair is the remodeling of the woven bone. Woven bone is initially formed as a temporary replacement for the fractured bone, but it is structurally weak and disorganized. Through the process of bone remodeling, the woven bone is gradually replaced by compact bone, which is stronger and more organized. This remodeling process involves the removal of excess bone tissue and the addition of new bone tissue, resulting in the restoration of the bone's normal structure and strength.
13.
The fracture type in which the bone ends are incompletely separated is:
Correct Answer
A. Greenstick
Explanation
A greenstick fracture is a type of fracture where the bone is partially broken and the ends are incompletely separated. This type of fracture is commonly seen in children because their bones are more flexible and less brittle than adults. In a greenstick fracture, the bone bends and cracks, but does not completely break. It is called "greenstick" because it is similar to bending a green stick, which will crack on the outside but remain intact on the inside.
14.
The disorder in which bones are porous and thin but bone composition is normal is:
Correct Answer
B. Osteoporosis
Explanation
Osteoporosis is a disorder characterized by porous and thin bones, despite having a normal bone composition. This condition occurs when the body loses too much bone mass or fails to produce enough bone, resulting in weak and brittle bones. Osteomalacia, on the other hand, is a condition where the bones become soft and weak due to a lack of vitamin D or calcium. Paget's disease is a condition where the bones become weak and deformed due to abnormal bone remodeling. Therefore, the correct answer is osteoporosis.
15.
______ is connected by the coronal suture.
Correct Answer
frontal bone and parietal bone
Explanation
The frontal bone and parietal bone are connected by the coronal suture. The coronal suture is a fibrous joint that runs horizontally across the skull, connecting the frontal bone (located at the front of the skull) and the parietal bone (located on the sides of the skull). This suture helps to join these two bones together, providing stability and strength to the skull.
16.
What structure is the keystone of the cranium?
Correct Answer
sphenoid bone
Explanation
The sphenoid bone is the keystone of the cranium because it is located in the center of the skull and forms a key supporting structure. It connects to multiple other bones in the cranium, including the frontal, parietal, temporal, and occipital bones. The sphenoid bone also houses important structures such as the pituitary gland and optic nerves. Its shape and position make it crucial for maintaining the stability and structure of the cranium.
17.
What structure is the keystone bone of the face?
Correct Answer
Maxillary
Explanation
The maxillary bone is the keystone bone of the face. It is the central bone that forms the upper jaw and the majority of the hard palate. It is responsible for supporting the other bones of the face and plays a crucial role in facial structure and function.
18.
Which structures form the hard palate?
Correct Answer
the maxillary bone and the palatine bone
Explanation
The hard palate is formed by the maxillary bone and the palatine bone. The maxillary bone is the main bone of the upper jaw, while the palatine bone is a small, L-shaped bone located behind the maxillary bone. Together, these two bones create the hard, bony structure that forms the roof of the mouth. This structure is important for various functions, including speech production and the separation of the oral and nasal cavities.
19.
What structure allows he spinal cord to pass?
Correct Answer
occipital bone
Explanation
The occipital bone is a structure located at the back of the skull. It forms the base of the skull and has a large opening called the foramen magnum. This opening allows the spinal cord to pass through and connect to the brain. Therefore, the occipital bone provides a pathway for the spinal cord to pass from the brain to the rest of the body.
20.
What structure forms the chin?
Correct Answer
mandible
Explanation
The mandible is the correct answer because it is the bone that forms the lower jaw and supports the chin. It is the largest and strongest bone in the face and plays a crucial role in functions such as biting, chewing, and speaking. The mandible also provides attachment points for various muscles involved in jaw movement.
21.
Which structures contain the paranasal sinuses?
Correct Answer
ethmoid, frontal, maxillary, sphenoid
Explanation
The paranasal sinuses are contained within the ethmoid, frontal, maxillary, and sphenoid bones. These structures are air-filled cavities located within the skull, surrounding the nasal cavity. The ethmoid sinuses are located between the eyes and behind the bridge of the nose, the frontal sinuses are located in the forehead region, the maxillary sinuses are located in the cheekbones, and the sphenoid sinuses are located behind the nasal cavity.
22.
Which structure contains the mastoid sinuses?
Correct Answer
temporal bone
Explanation
The mastoid sinuses are located within the temporal bone. The temporal bone is a paired bone that forms part of the skull, specifically the sides and base of the cranium. It houses various structures including the mastoid process, which contains the mastoid sinuses. These sinuses are air-filled spaces that are important for the drainage of the middle ear and play a role in the resonance of sound. Therefore, the correct answer is the temporal bone.
23.
Bone of the axial skeleton to which the pectoral girdle attaches?
Correct Answer
Sternum
Explanation
The sternum is a bone located in the middle of the chest that forms the front part of the rib cage. It is part of the axial skeleton, which includes the bones of the head, neck, and trunk. The pectoral girdle, also known as the shoulder girdle, consists of the clavicle and scapula, and it attaches to the sternum. Therefore, the sternum is the bone to which the pectoral girdle attaches.
24.
Markings include glenoid cavity and acromion?
Correct Answer
Scapula
Explanation
The scapula is a triangular-shaped bone that is part of the shoulder girdle. It is marked by the presence of the glenoid cavity, which is a shallow socket that articulates with the head of the humerus to form the shoulder joint. The acromion is a bony process that extends from the scapula and forms the highest point of the shoulder. These markings are important for the attachment of muscles and ligaments, as well as for the movement and stability of the shoulder joint. Therefore, the scapula is the correct answer as it includes both the glenoid cavity and the acromion.
25.
Features include the ala, crest and greater sciatic notch?
Correct Answer
illium
Explanation
The ilium is one of the three bones that make up the pelvic girdle. It features several distinct anatomical landmarks, including the ala, crest, and greater sciatic notch. The ala refers to the broad, wing-like portion of the ilium that contributes to the overall shape of the pelvis. The crest is a prominent ridge that runs along the top of the ilium, providing attachment points for muscles. The greater sciatic notch is a large notch located on the posterior aspect of the ilium, allowing for the passage of nerves and blood vessels. Therefore, the correct answer is ilium.
26.
Doubly curved; acts as a shoulder strut?
Correct Answer
Clavicle
Explanation
The clavicle, also known as the collarbone, is a bone in the human body that is doubly curved. Its shape resembles an "S" or an elongated "S" and acts as a shoulder strut. The clavicle connects the shoulder blade to the sternum, providing stability and support to the shoulder joint. Its curved structure allows for a wide range of motion in the shoulder and helps to protect important structures beneath it.
27.
Pelvic girdle bone that articulates with the axial skeleton?
Correct Answer
ilium
Explanation
The ilium is a pelvic girdle bone that articulates with the axial skeleton. It is the largest and uppermost part of the hip bone, forming the prominence of the hip. It connects with the sacrum at the sacroiliac joint, which is part of the axial skeleton. The ilium plays a crucial role in supporting the weight of the upper body and transferring it to the lower limbs.
28.
The "sit-down" bone?
Correct Answer
Ischium
Explanation
The ischium is one of the three bones that make up the hip bone. It is commonly referred to as the "sit-down" bone because it is the bone that bears most of the body's weight when sitting. The ischium forms the lower and back part of the hip bone and provides support and stability to the pelvis.
29.
Anteriormost bone of the pelvic girdle?
Correct Answer
Pubis
Explanation
The pubis is the correct answer because it is the anteriormost bone of the pelvic girdle. The pelvic girdle is made up of three bones: the ilium, ischium, and pubis. The pubis is located at the front of the pelvis, connecting to the other two bones at the acetabulum. It helps to support the weight of the upper body and provides attachment points for muscles and ligaments involved in movement and stability of the pelvis.
30.
Part of the vertebral column?
Correct Answer
Sacrum
Explanation
The sacrum is a part of the vertebral column located at the base of the spine, between the lumbar vertebrae and the coccyx. It is a triangular bone formed by the fusion of five vertebrae and serves as a strong foundation for the pelvis. The sacrum provides stability and support to the spine and helps to transfer weight from the upper body to the lower limbs.
31.
Articulates with the acetabulum and the tibia?
Correct Answer
Femur
Explanation
The femur is the correct answer because it articulates with both the acetabulum (socket of the hip bone) and the tibia (shin bone). This means that the femur forms a joint with both of these bones, allowing for movement and stability in the hip and knee joints.
32.
Forms the lateral aspect of the ankle?
Correct Answer
Fibula
Explanation
The fibula is a bone in the lower leg that forms the lateral aspect of the ankle. It is located on the outer side of the leg and runs parallel to the tibia, which forms the medial aspect of the ankle. The fibula helps to provide stability and support to the ankle joint, along with the tibia.
33.
Bone that "carries" the hand?
Correct Answer
Radius
Explanation
The radius is the bone in the forearm that is responsible for carrying the hand. It is located on the thumb side of the arm and runs parallel to the ulna. The radius plays a crucial role in allowing the hand to rotate and pivot, enabling movements such as turning the palm up or down.
34.
The wrist bones?
Correct Answer
Carpals
Explanation
Carpals are the small bones located in the wrist. They form the wrist joint and provide stability and flexibility to the hand. The carpals consist of eight bones arranged in two rows. These bones allow for movements such as flexion, extension, and rotation of the wrist. They also provide support for the hand and allow for the transmission of forces from the hand to the forearm.
35.
End shaped like a monkey wrench?
Correct Answer
Ulna
Explanation
The ulna is one of the two bones in the forearm, along with the radius. It is responsible for forming the joint at the elbow and plays a crucial role in the movement of the forearm and hand. The ulna has a distinct shape, with a curved body and a bony prominence called the olecranon process that resembles the handle of a monkey wrench. This unique shape of the ulna allows for the attachment of muscles and ligaments, providing stability and strength to the elbow joint.
36.
Articulates with the capitulum of the humerus?
Correct Answer
Radius
Explanation
The radius articulates with the capitulum of the humerus. This means that the radius bone connects with the rounded end of the humerus bone at the elbow joint. The articulation between these two bones allows for movement and rotation of the forearm.
37.
Largest bone of this "group" is the calcaneus?
Correct Answer
tarsals
Explanation
The calcaneus is indeed the largest bone in the group of tarsals. The tarsals are a group of seven bones located in the foot, including the calcaneus, talus, navicular, cuboid, and three cuneiform bones. Among these, the calcaneus is the largest and plays a crucial role in weight-bearing and walking. It forms the heel bone and provides stability and support to the foot. Therefore, tarsals is the correct answer as it includes the calcaneus, which is the largest bone in this group.
38.
Which type of joint exhibits a joint cavity?
Correct Answer
Synovial joints
Explanation
Synovial joints exhibit a joint cavity. These joints are characterized by the presence of a synovial membrane that secretes synovial fluid, which fills the joint cavity. The joint cavity allows for smooth movement and reduces friction between the articulating surfaces of the bones. Examples of synovial joints include the knee, shoulder, and hip joints.
39.
Types are sutures and syndesomes?
Correct Answer
Fibrous joints
Explanation
Fibrous joints are a type of joint where the bones are connected by fibrous connective tissue. This type of joint allows for little to no movement, providing stability and support to the bones. Sutures and syndesmoses are both examples of fibrous joints. Sutures are found in the skull and are immovable, while syndesmoses are found in the lower leg and allow for a small amount of movement. Thus, the correct answer is fibrous joints.
40.
Bones connected by collagen fibers?
Correct Answer
fibrous joints
Explanation
Fibrous joints are formed by bones connected by collagen fibers. These joints are immovable and provide stability and strength to the skeletal system. The collagen fibers in fibrous joints allow for minimal movement and provide a strong connection between the bones. Examples of fibrous joints include sutures in the skull and syndesmoses in the lower leg.
41.
Types include snychondroses and symphyses?
Correct Answer
Cartilaginous joints
Explanation
Cartilaginous joints are a type of joint in the skeletal system that are connected by cartilage. There are two main types of cartilaginous joints: synchondroses and symphyses. Synchondroses are joints where the bones are connected by hyaline cartilage, such as the joints between the ribs and sternum. Symphyses are joints where the bones are connected by fibrocartilage, such as the pubic symphysis in the pelvis. These types of joints provide stability and limited movement between the bones they connect.
42.
All are diathrotic?
Correct Answer
Synovial joints
43.
Many are amphiarthrotic?
Correct Answer
Cartilaginous joints
Explanation
Cartilaginous joints are the correct answer because they are a type of joint that allows limited movement, making them amphiarthrotic. These joints are connected by cartilage, which provides flexibility and shock absorption. Examples of cartilaginous joints include the joints between the vertebrae in the spine and the pubic symphysis.
44.
Bones connected by a disc of hyaline cartilage or fibrocartilage?
Correct Answer
Cartilaginous joints
Explanation
Cartilaginous joints are bones connected by a disc of hyaline cartilage or fibrocartilage. These joints allow for limited movement and provide stability to the skeletal system. The type of cartilage present in these joints can vary depending on the specific joint and its function. Hyaline cartilage is found in joints where slight movement is required, while fibrocartilage is present in joints that need more stability and strength, such as the intervertebral discs in the spine.
45.
Nearly all are synarthrotic?
Correct Answer
Fibrous joints
Explanation
Fibrous joints are characterized by the presence of fibrous connective tissue between the bones, which allows for very little to no movement. This type of joint is also known as a synarthrosis, meaning it is immobile or nearly immobile. Therefore, the statement suggests that nearly all fibrous joints are synarthrotic, meaning they have limited or no movement.
46.
Shoulder, hip, law and elbow joints?
Correct Answer
Synovial joints
Explanation
The question is asking for the type of joints that include the shoulder, hip, jaw, and elbow joints. The correct answer is "Synovial joints." Synovial joints are characterized by the presence of a fluid-filled synovial cavity between the articulating surfaces of the bones. These joints allow for a wide range of movement and are found in the shoulder, hip, jaw, and elbow joints, among others.
47.
Freely movable joints are:
Correct Answer
B. Diarthroses
Explanation
Diarthroses are freely movable joints. These joints have a wide range of motion and are commonly found in the limbs. They are characterized by the presence of a synovial cavity, which is filled with synovial fluid that lubricates the joint and reduces friction. Diarthroses allow for smooth and fluid movements, such as bending, straightening, and rotating. Examples of diarthroses include the shoulder joint, hip joint, and knee joint.
48.
Anatomical characteristics of a synovial joint include:
Correct Answer
D. All of these
Explanation
The anatomical characteristics of a synovial joint include articular cartilage, a joint cavity, and an articular capsule. Articular cartilage covers the ends of the bones, allowing smooth movement and reducing friction. The joint cavity is a space filled with synovial fluid, which lubricates the joint and provides nutrients to the cartilage. The articular capsule surrounds the joint, providing stability and containing the synovial fluid. Therefore, all of these characteristics are present in a synovial joint.
49.
Factors that influence the stability of a synovial joint include:
Correct Answer
D. All of these
Explanation
The stability of a synovial joint is influenced by multiple factors. The shape of the articular surfaces plays a crucial role as it determines how well the bones fit together and the range of motion allowed. The presence of strong reinforcing ligaments provides additional support and prevents excessive movement or dislocation of the joint. Additionally, the tone of the surrounding muscles helps stabilize the joint by providing dynamic support and controlling its movement. Therefore, all of these factors contribute to the overall stability of a synovial joint.
50.
The description "articular surfaces deep and secure; capsule heavily reinforced by ligaments and muscle tendons; extremely stable joint" best describes:
Correct Answer
B. The hip joint
Explanation
The description "articular surfaces deep and secure; capsule heavily reinforced by ligaments and muscle tendons; extremely stable joint" best describes the hip joint. The hip joint is known for its deep and secure articular surfaces, which provide stability. The capsule of the hip joint is heavily reinforced by ligaments and muscle tendons, further enhancing its stability. Overall, the hip joint is considered to be extremely stable compared to other joints in the body.