1. A journey into the body’s most important function.
The Heart
By Derek.Herridge
Block D. Mr.T
A journey into the body’s most important function.

2. Structure of The Heart
The heart is a very complicated organ. In order to understand it more, people draw diagrams that show it’s stucture.

3. Location
In the human body, the heart is normally situated in the left of the middle of the thorax, underneath the breastbone. The heart is usually felt on the left side because the left ventricle is stronger. The left lung is also smaller than the right lung because the heart occupies most of the left hermithorax.

4. Heartbeat
The heart works as a pump to send oxygen rich blood throughout the body. A human heart beats on average of times per day. In that time, it pumps more than 4300 gallons of blood throughout the entire body. The human body has about 5.6 liters of blood, all of which circulates through the body three times every minute.

5. Cycle of the Blood
The hearts cycle starts when oxygen poor blood from the body flows into the right atrium. Next, blood flows through the right atrium to the right ventricle, which serves as a pump that sends blood to the lungs. Within the lungs, the blood releases waste gasses and picks up oxygen. This newly oxygen enriched blood returns from the lungs to the left atrium. Then blood flows from the left atrium to the left ventricle. Finally, the left ventricle pumps blood all throughout the body.

6. Structures of the Heart Part 1
Superior vena cava: One of the two main veins bringing deoxygenated blood from the body to the heart. Brings blood from upper body.
Inferior vena cava : One of the two main veins bringing deoxygenated blood from the body to the heart. Brings blood from lower body.
Right Atrium: The upper right chamber of the heart. Receives deoxygenated blood from the superior vena cava and the inferior vena cava. Blood here flows to the right ventricle through the open tricuspid valve.
Right Ventricle: The lower right chamber of the heart. Receives blood from the right atrium as it contracts. Then sends blood to the lungs to be reoxygenized. The right and left ventricles contract simultaneously, but because the right ventricle is thinner than the left, it produces a lower pressure than the left when contracting.

7. Structures of the Heart Part 2
Aorta: The central conduit from the heart to the body, the aorta carries oxygenated blood from the left ventricle to various parts of the body as the left ventricle contracts.
Left Atrium: The upper left chamber of the heart. The left atrium receives oxygenated blood from the lungs through the pulmonary veins. Then sends blood to left ventricle.
Left Ventricle: The lower left chamber of the heart, receives oxygenated blood from the left atrium. The left and right ventricles contract simultaneously, however, because the left ventricle is thicker than the right, it produces a higher pressure than the right when contracting. The higher pressure is necessary to pump blood through the body.
Tricuspid Valve: One of the four one way valves that keeps blood flowing properly through the various chambers of the heart. Standing between the right atrium and the left ventricle, the tricuspid valve is the first valve that blood encounters as it enters the heart.

8. Structures of Heart part 3
Aortic Valve: One of the four one way valves that keeps blood flowing properly through the various chambers of the heart. The aortic valve separates the left ventricle from the aorta.
Mitral Valve: One of the four one way valves that keeps blood flowing through the various chambers of the heart. The mitral valve separates the left atrium from the left ventricle.
Septum: The wall between the two upper chambers of the heart( the left and right atrium.)
Pulmonary Artery: The pulmonary arteries carry blood from the heart to the lungs and vise versa.

9. The Heart Muscle
A powerful muscle slightly larger than a clenched fist. It is composed of four chambers and sends oxygen rich blood throughout the body.

10. Heart disease and problems
There are a number of different heart diseases that one could obtain from various effects such as smoking. Smoking is very dangerous for the body’s heart and lungs because it is filled with deadly poisons.

11. M.U.G.A scans of heart
MUGA scans allow doctors to see if everything is functioning properly in a persons heart. Its done by injecting a substance in the blood stream that is sensitive to radioactive waves, then once the waves enter and leave the heart, doctors can see if a persons heart is functioning normally.

12. Ultrasound Scans of heart
Ultrasound is another way to check the heart functioning. Basically, a machine emits sound than has enough depth to penetrate some organs, and not others

13. M.R.I Scan
M.R.I stands for magnetic resonance imaging. It is a fairy new technique that has been used since the 1980’s. The M.R.I uses magnetic radio waves, meaning there is no exposure to X-rays, or another form of dangerous radiation.

14. The End