Page 12 - Human anatomy COMPLETELY DONE1

external breathing is carried out.
The number of pairs of ribs in a person is 12. From behind, they are semi-
movably connected to the vertebrae.
The seven upper ribs are also semi-movably connected to the breastbone, or
sternum.
The ribs numbered 8, 9, 10 are connected through cartilage to the overlying ribs.
The front ends of the 11th and 12th pairs of ribs end freely in the muscles.
The sternum consists of a handle to which the collarbones are attached, a body
to which the first seven pairs of ribs are attached, and an xiphoid process.
The skeleton of the shoulder girdle and upper limbs
The skeleton of the shoulder girdle connects the skeleton of the arms with the
rest of the skeleton. It consists of two shoulder blades and two collarbones (figure 6).

collarbone

shoulder
blade

Figure 6. Shoulder blade and collarbone

Shoulder blades are flat triangular bones located on the back side of the chest.

The shoulder blades are attached to the collarbones.
The collarbones are S-shaped bones connected to the sternum and shoulder blade.
The skeleton of the pelvic girdle and lower extremities
The skeleton of the pelvic girdle connects the skeleton of the legs with the spine.
The pelvic girdle is formed by the fusion of two iliac, two sciatic and two pubic
bones. At the junction of these bones is the acetabulum, which includes the head of the
femur. You can see Pelvis Girdle Anterior and Posterior view (figure 7).
The pelvic bones are connected to the sacrum in a very strong structure – the
pelvis. It is a bony ring, inside of which there is a cavity. The vertebral column rests on
the pelvis, and the flat bones forming it support and protect the internal organs located
in the abdominal cavity.

12