Body Cavity

BODY CAVITY:

Thoracic Cavity:

Thoracic cavity is the 2^nd in point of size among the body cavities .In form its somewhat like truncated cone,much compressed laterally. Its cranial part and with the base cut off obliquely. Dorsal wall {roof } is formed by the Thoracic vertebrae and ITS the ligament connect with them .Lateral wall is formed by the ribs and Intercostal Musclee.

Ventral wall or floor is formed by STERNUM.

Caudal wall=Diaphragm,is very obligque and convex.

Creanial part is relatively small and narrow,OVAL form.

Its 0ccupied by the longus coli muscle, Trachia,Esophagus ,Vessels , Nerves and Lymph nodes.

A longitudinal septum divides  the cavity into two lateral chambers .       Each  chamber is lined by  serus membrane, called Pleura . It is termed as pleural cavity .
The largest and soft organs include heart ,lung , are situated in this cavity.

Abdominal Cavity;

The Abdominal Cavity is largest . Separated From the thoracic cavity by DGAPHRAGM .Caudaly with pelvic cavity.There is a line between abdomen and pelvic cavity known as terminal line or brim of pelvis.Dorsally its by the base of the sternum. The accurate lines laterally and cranial border of pubic bone ventraly.

Ovoid Shape.compressed laterally. The dorsal wall is formed by the lumber vertebrae,the iumber muscle and lumber part of diaphragm.The lateral walls are formed by the oblique and trans verse abdominal muscle, abdominal facia andcartilages of the asternal ribs .Ventral wall consist of 2 recti,the aponenuroses of oblique and transverse muscle, the abdominal facia the xiphoid cartilage.

Pelvic cavity is the caudal part of the trunk. It encloses   the pelvic cavity which communicates cranially with the abdominal cavity,there is a line of demarcation being the terminal line or pelvic brim.The dorsal wall is formed by the sacrum and first few cocygeal(caudal)vertebrae.The lateral walls are formed by the iliopectineal lines and the sacrotubera ligament.Theventral wall is formed by the pubic and ischial bones.The cavity contains the rectum,parts of the internal genital and urinary organs,some fetal remnants,muscles,vessels and nerves.It is lined by the pelvic facia and in part by the peritoneum