Skeletal system

Question 1

Cranium

Answer 1

The skull is a bony structure that forms the head in most vertebrates. It supports the structures of the face and provides a protective cavity for the brain. The skull is composed of two parts: the cranium and the mandible.

Question 2

Mandible

Answer 2

The mandible, lower jaw or jawbone is the largest, strongest and lowest bone in the face. It forms the lower jaw and holds the lower teeth in place. The mandible sits beneath the maxilla. The mandible is the only movable bone of the skull besides the ossicles of the middle ear.

Question 3

Clavicle

Answer 3

The clavicle or collarbone is a long bone that serves as a strut between the shoulder blade and the sternum or breastbone. There are two clavicles, one on the left and one on the right. The clavicle is the only long bone in the body that lies horizontally. Together with the shoulder blade it makes up the shoulder girdle.

Question 4

Sternum

Answer 4

The sternum or breastbone is a long flat bone shaped like a necktie located in the center of the chest. It connects to the ribs via cartilage, forming the front of the rib cage, and thus helps to protect the heart, lungs, and major blood vessels from injury. The sternum consists of three regions: the manubrium, the body, and the xiphoid process. It is one of the largest and longest flat bones of the body.

Question 5

Scapula

Answer 5

The scapula (a.k.a. shoulder blade or wing bone), is the bone that connects the humerus (upper arm bone) with the clavicle (collar bone). Like their connected bones the scapulae are paired, with the scapula on the left side of the body being roughly a mirror image of the right scapula.

Question 6

Humerus

Answer 6

The humerus is a long bone in the arm or forelimb that runs from the shoulder to the elbow. It connects the scapula and the two bones of the lower arm, the radius and ulna, and consists of three sections. The humeral upper extremity consists of a rounded head, a narrow neck, and two short processes (tubercles, sometimes called tuberosities).

Question 7

Ribcage

Answer 7

The rib cage, also known as the thoracic cage, is a bony and cartilaginous structure which surrounds the thoracic cavity and supports the pectoral girdle (shoulder girdle), forming a core portion of the human skeleton. A typical human rib cage consists of 24 ribs, the sternum (with xiphoid process), costal cartilages, and the 12 thoracic vertebrae. Together with the skin and associated fascia and muscles, the rib cage makes up the thoracic wall and provides attachments for the muscles of the neck, thorax, upper abdomen, and back.

Question 8

Spine

Answer 8

The vertebral column, also known as the backbone or spine, is part of the axial skeleton. The vertebral column houses the spinal canal, a cavity that encloses and protects the spinal cord.

Question 9

Radius

Answer 9

The radius or radial bone is one of the two large bones of the forearm, the other being the ulna. It extends from the lateral side of the elbow to the thumb side of the wrist and runs parallel to the ulna. The radius is shorter and smaller than the ulna. It is a long bone, prism-shaped and slightly curved longitudinally.

Question 10

Ulna

Answer 10

The ulna is a long bone found in the forearm that stretches from the elbow to the smallest finger, and when in anatomical position, is found on the medial side of the forearm. It runs parallel to the radius, the other long bone in the forearm, and is the larger and longer of the two.

Question 11

Coxal bone

Answer 11

The hip bone is a large flat bone, constricted in the center and expanded above and below. The two hip bones join at the pubic symphysis and together with the sacrum and coccyx (the pelvic part of the spine) comprise the skeletal component of the pelvis – the pelvic girdle which surrounds the pelvic cavity.

Question 12

Sacrum

Answer 12

The sacrum in human anatomy is a large, triangular bone at the base of the spine, that forms by the fusing of sacral vertebrae S1–S5 between 18 and 30 years of age. The sacrum is situated at the upper, back part of the pelvic cavity, between the two wings of the pelvis. It forms joints with four other bones.

Question 13

Coccyx

Answer 13

The coccyx, commonly referred to as the tailbone, is the final segment of the vertebral column. It comprises three to five separate or fused coccygeal vertebrae below the sacrum, attached to the sacrum by a fibrocartilaginous joint, the sacrococcygeal symphysis, which permits limited movement between the sacrum and the coccyx.

Question 14

Carpals

Answer 14

The carpal bones are the eight small bones that make up the wrist (or carpus) that connects the hand to the forearm. In human anatomy, the main role of the wrist is to facilitate effective positioning of the hand and powerful use of the extensors and flexors of the forearm. The mobility of individual carpal bones increases the freedom of movements at the wrist.

Question 15

Metacarpals

Answer 15

In human anatomy, the metacarpal bones or metacarpus, form the intermediate part of the skeletal hand located between the phalanges of the fingers and the carpal bones of the wrist which forms the connection to the forearm. The metacarpal bones are equivalent to the metatarsal bones in the foot.

Question 16

Phalanges

Answer 16

The phalanges are digital bones in the hands and feet. The thumbs and big toes have two phalanges while the other digits have three phalanges. The phalanges are classed as long bones.

Question 17

Femur

Answer 17

The femur or thigh bone, is the most proximal (closest to the hip joint) bone of the leg. The head of the femur articulates with the acetabulum in the pelvic bone forming the hip joint, while the distal part of the femur articulates with the tibia and kneecap forming the knee joint. By most measures the femur is the strongest bone in the body. The femur is also the longest bone in the body.

Question 18

Patella

Answer 18

The patella, also known as the kneecap, is a thick, circular-triangular bone which articulates with the femur (thigh bone) and covers and protects the anterior articular surface of the knee joint.

Question 19

Fibula

Answer 19

The fibula or calf bone is a leg bone located on the lateral side of the tibia, and connects to it above and below. It is the smaller of the two bones, and, in proportion to its length, the slenderest of all the long bones. Its upper extremity is small, placed toward the back of the head of the tibia, below the level of the knee joint, and excluded from the formation of this joint. Its lower extremity inclines a little forward, so as to be on a plane anterior to that of the upper end; it projects below the tibia, and forms the lateral part of the ankle joint.

Question 20

Tibia

Answer 20

The tibia, also known as the shinbone or shankbone, is the larger and stronger of the two bones in the leg below the knee, and it connects the knee with the ankle bones. The tibia is found on the medial side of the leg next to the fibula and closer to the median plane or center line. The tibia is connected to the fibula by the interosseous membrane of the leg, forming a type of fibrous joint called a syndesmosis with very little movement.