As shown in the figure:

Heart: The heart of a normal adult is slightly larger than a fist, weighs about 300 grams, is slightly conical in shape, and is located between the two lungs on the diaphragm, slightly to the center of the chest. On the left, the apex of the heart is at the lower left. The heart is divided into four chambers, the left and right atria and the left and right ventricles, which are separated by the interatrial septum and the ventricular septum respectively. The left and right chambers are not connected to each other.

Liver: Most of the human liver is located in the right rib and upper abdomen, and a small part is located in the left rib area. Its upper limit is at the level of the right midclavicular line and the fifth rib. The upper part is close to the diaphragm and connected with the right lung. It is adjacent to the heart; below it is adjacent to the stomach, duodenum, and right flexure of the colon; behind it is in contact with the right kidney, adrenal gland, and esophageal cardia. It is the largest gland in the human body.

Spleen: The spleen is an important lymphoid organ. It is located in the upper left side of the abdominal cavity. It is flat and oval in shape, dark red, soft and brittle. It can easily rupture and bleed when it is violently hit locally. The spleen is located between the fundus of the stomach and the diaphragm in the left quarter rib area, just opposite the 9th to 11th ribs, and its long axis is consistent with the 10th rib.

Lungs: The lungs are the respiratory organs of the human body and also the important blood-forming organs of the human body. They are located in the chest, one on the left and one on the left, covering the heart.

Kidneys: The kidneys are located on both sides of the spine, close to the posterior abdominal wall, and behind the peritoneum. The upper end of the left kidney is level with the lower edge of the 11th thoracic vertebra, and the lower end is level with the lower edge of the 2nd lumbar vertebra. The right kidney is half a vertebra lower than the left kidney. The left 12th rib runs obliquely across the middle part behind the left kidney, and the right 12th rib runs obliquely across the upper part behind the right kidney.

Extended information:

Physiological functions of the spleen:

1. The spleen is the "blood bank" of the human body. When the human body is resting and quiet, it stores blood. When in stress states such as exercise, blood loss, and hypoxia, it discharges blood into the blood circulation to increase blood volume.

2. The spleen is like a "filter". When germs, antigens, foreign bodies, and protozoa appear in the blood, the macrophages and lymphocytes in the spleen will eat them.

3. The spleen can also produce immune substances such as immunoglobulin and complement to exert immune effects. The spleen is an important filter in the blood circulation. It can remove foreign matter, germs and aging and dead cells in the blood, especially red blood cells and platelets. Therefore, hypersplenism may cause a decrease in red blood cells and platelets.

4. The spleen also has the function of producing lymphocytes.

Baidu Encyclopedia - Human Organs

Baidu Encyclopedia - Heart

Baidu Encyclopedia - Liver

Baidu Encyclopedia - Spleen

Baidu Encyclopedia—Lung

Baidu Encyclopedia—Kidney