Place your hand between the dogs front legs and you will find the breast-bone [sternum] where the ribs from both sides join. Find the base of the sternum where the last 2 ribs join it. Just above your hand are the lungs and just behind the base of the left lung is the heart quite close to the base of the sternum.
Your lungs are around the area of your chest.
The sternum is part of the chest skeleton system, it has nothing to do with the heart.
The heart is in the thoracic cavity in a part called the mediastinum. It is protected by the pericardium, a membranous sac that surround the heart. The mediastinum is that space in the thoracic cavity between the lungs that contains the heart. It also contains the aorta, esophagus, trachea and thymus.The pleural cavity is the space in the chest between the lungs.
The part of the body enclosed by the ribs and sternum is the thorax or chest cavity. This cavity contains the heart, lungs, and other vital organs that help with breathing and circulation. It plays a crucial role in protecting these organs and supporting proper respiratory function.
hChest. hheart.
the heart
left
The heart is approximately the size of your fist and is located in the middle/left part of your chest.
it is along the back part of an ant body
Imago
The heart contains atrium
Your chest contains many organs, like the heart, lungs with its pleural covering, esophagus, muscles, ribs, tendons, and nerves. They all can be the source of the pain that you are feeling. It could be a hiatal hernia, muscle exertion, etc. You probably should see your doctor if the pain is severe and doesn't go away.