The Musculoskeletal System I

Question 1

Appendicular
skeleton

Answer 1

The appendicular skeleton is the part of the human skeleton that includes the bones of the limbs and their attachments to the body. It consists of the upper limbs (humerus, radius, ulna, and bones of the hand) and lower limbs (femur, tibia, fibula, and bones of the foot), along with the pectoral girdle (clavicles and scapulae) and the pelvic girdle (hip bones). This skeleton is essential for movement and mobility, providing support for physical activities and facilitating a wide range of motions

Question 2

Occipital
bone

Answer 2

The occipital bone is a trapezoidal bone located at the back and base of the skull, featuring the foramen magnum for the spinal cord and occipital condyles that articulate with the first cervical vertebra to allow head movement.

Question 3

Humerus

Answer 3

The humerus is the long bone of the upper arm, extending from the shoulder to the elbow, and it plays a crucial role in arm movement and stability.

Question 4

Pivot joint

Answer 4

A pivot joint is a type of synovial joint that allows for rotational movement around a single axis, enabling one bone to rotate around another. Examples include the atlantoaxial joint between the first two cervical vertebrae (allowing for head rotation) and the proximal radioulnar joint (allowing the radius to rotate around the ulna during pronation and supination of the forearm).

Question 5

Foramen
magnum

Answer 5

The foramen magnum is a large opening at the base of the skull, located in the occipital bone, through which the spinal cord passes to connect with the brain. It allows for the transition of neural and vascular structures between the cranial cavity and the vertebral canal, playing a crucial role in the central nervous system’s functionality

Question 6

Spongy
bone

Answer 6

Spongy bone, also known as cancellous or trabecular bone, is a type of bone tissue characterized by a porous, lattice-like structure that contains numerous small cavities.

Key Features:
Location: It is primarily found at the ends of long bones (such as the femur and humerus), in the interior of vertebrae, and within the structure of flat bones (like the skull).
Function: Spongy bone helps reduce the weight of bones while still providing strength and support; it also houses bone marrow, where blood cell production occurs.
Composition: The trabecular structure allows for the distribution of forces and provides flexibility, making it less dense than compact bone, which surrounds and protects it.
Overall, spongy bone plays a crucial role in bone health and function by providing support, flexibility, and a site for hematopoiesis (blood cell formation).

Question 7

Synovial joint

Answer 7

A synovial joint is a type of joint characterized by a fluid-filled cavity (synovial cavity) that allows for a wide range of movement between the articulating bones, providing lubrication and reducing friction; examples include the knee, elbow, and shoulder joints

Question 8

Radius

Answer 8

The radius is one of the two long bones in the forearm, located on the lateral side (thumb side) of the arm, extending from the elbow to the wrist, and plays a crucial role in the movement and rotation of the forearm.

Question 9

Vertebral
column

Answer 9

The vertebral column, also known as the spine or backbone, is a flexible structure composed of 33 vertebrae that provides support for the body, protects the spinal cord, and allows for a range of movements, including bending and twisting

Question 10

Axial skeleton

Answer 10

The axial skeleton is the central framework of the human skeleton, consisting of 80 bones that include the skull, vertebral column, and rib cage, providing support and protection for the brain, spinal cord, and vital organs in the thorax.

Question 11

Extension

Answer 11

Extension is a movement that increases the angle between two body parts, typically straightening a joint; for example, extending the elbow involves straightening the arm from a flexed position

Question 12

Ulna
The ulna is one of the two long bones in the forearm, located on the medial side (pinky side) of the arm, extending from the elbow to the wrist, and it plays a key role in forming the elbow joint and providing stability to the forearm.

Question 13

Compact Bone

Answer 13

Compact bone is a dense and strong type of bone tissue that forms the outer layer of bones, providing structural support and protection, as well as housing the Haversian systems (osteons) that contain blood vessels and nerves.

Question 14

Sagittal Suture

Answer 14

The sagittal suture is a fibrous joint that runs along the top of the skull, separating the left and right parietal bones; it extends from the front (frontal bone) to the back (occipital bone) of the skull and plays a crucial role in the structural integrity of the cranium.