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THE HEART
             Kimberly Cai CN-3
       Stephanie Syjueco CN-22
WHAT IS THE HEART?

The  heart is the organ that
 supplies blood and oxygen
 to all parts of the body.
The heart is pear shaped
 and about the size of a fist.
Theheart is an
involuntary muscle,
meaning that unlike the
leg or arm muscles, the
cardiac muscle is not
under voluntary control.
WHERE IS THE HEART LOCATED?

The    heart is located
 beneath the protective ribs
 on the left side.
It is located in the chest
 cavity
It is surrounded by a
 covering called the
 pericardium.
THE HEART

The  heart is divided into
 four chambers, called the
 right and left atria and
 the right and left
 ventricles
DIFFERENT ANIMALS MAY HAVE DIFFERENT
CHAMBERED HEARTS OR NONE AT ALL.
FOLLOWING IS THE GENERAL ANATOMY OF
THE HUMAN HEART.
PARTS OF THE HEART
MAIN FUNCTIONS OF THE HEART
   The role of the heart is to pump oxygen-rich
    blood to every living cell in the body. In order
    to achieve its goal, it must continuously beat
    for a person’s entire lifespan. Because of its
    vital role, a non-beating heart always results in
    death
   The heart beats almost like a clock, about 60 to
    80 times per minute, CONTINUOUSLY, whether
    you are asleep or awake. The heartbeat is
    regulated by a small "battery" located in the
    right atrium called the SINUS NODE. Electric
    currents travel in the heart by means of minute
    fiber's in the wall of the heart, much like
    concealed wiring inside a room.
THE HEARTBEAT

The  heartbeat is made up
 of systole and diastole,
 which are the two stages of
 a heartbeat.
SYSTOLE
 Stage when the ventricles of heart are
  contracting resulting in blood being pumped
  out to the lungs and the rest of the body.
 Thick, muscular walls of both ventricles
  contract.
 Pressure rises in both ventricles, causing the
  bicuspid and tricuspid valves to close.
  Therefore, blood is forced up the aorta and the
  pulmonary artery.
 The atria relax during this time. The left atrium
  receives blood from the pulmonary vein, and
  the right atrium from the vena cava.
DIASTOLE
 Stage when the ventricles of the heart are
  relaxed and not contracting. During this stage,
  the atria are filled with blood and pump blood
  into the ventricles.
 Thick, muscular walls of both ventricles relax.

 Pressure in both ventricles falls low enough for
  bicuspid valves to open.
 The atria contract, and blood is forced into the
  ventricles, expanding them.
 The blood pressure in the aorta is decreased,
  therefore the semi-lunar valves close.
THANKS FOR LISTENING! 

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15. the heart

  • 1. THE HEART Kimberly Cai CN-3 Stephanie Syjueco CN-22
  • 2. WHAT IS THE HEART? The heart is the organ that supplies blood and oxygen to all parts of the body. The heart is pear shaped and about the size of a fist.
  • 3. Theheart is an involuntary muscle, meaning that unlike the leg or arm muscles, the cardiac muscle is not under voluntary control.
  • 4.
  • 5. WHERE IS THE HEART LOCATED? The heart is located beneath the protective ribs on the left side. It is located in the chest cavity It is surrounded by a covering called the pericardium.
  • 6.
  • 7. THE HEART The heart is divided into four chambers, called the right and left atria and the right and left ventricles
  • 8. DIFFERENT ANIMALS MAY HAVE DIFFERENT CHAMBERED HEARTS OR NONE AT ALL. FOLLOWING IS THE GENERAL ANATOMY OF THE HUMAN HEART.
  • 9. PARTS OF THE HEART
  • 10. MAIN FUNCTIONS OF THE HEART  The role of the heart is to pump oxygen-rich blood to every living cell in the body. In order to achieve its goal, it must continuously beat for a person’s entire lifespan. Because of its vital role, a non-beating heart always results in death
  • 11. The heart beats almost like a clock, about 60 to 80 times per minute, CONTINUOUSLY, whether you are asleep or awake. The heartbeat is regulated by a small "battery" located in the right atrium called the SINUS NODE. Electric currents travel in the heart by means of minute fiber's in the wall of the heart, much like concealed wiring inside a room.
  • 12. THE HEARTBEAT The heartbeat is made up of systole and diastole, which are the two stages of a heartbeat.
  • 13. SYSTOLE  Stage when the ventricles of heart are contracting resulting in blood being pumped out to the lungs and the rest of the body.  Thick, muscular walls of both ventricles contract.  Pressure rises in both ventricles, causing the bicuspid and tricuspid valves to close. Therefore, blood is forced up the aorta and the pulmonary artery.  The atria relax during this time. The left atrium receives blood from the pulmonary vein, and the right atrium from the vena cava.
  • 14. DIASTOLE  Stage when the ventricles of the heart are relaxed and not contracting. During this stage, the atria are filled with blood and pump blood into the ventricles.  Thick, muscular walls of both ventricles relax.  Pressure in both ventricles falls low enough for bicuspid valves to open.  The atria contract, and blood is forced into the ventricles, expanding them.  The blood pressure in the aorta is decreased, therefore the semi-lunar valves close.