Heart and the Circulatory System

• The body has its own transport system that carries substances around the body.
• The body's transport system is also called as the circulatory system.
• Two gases are transported to/from the body' cells which are Oxygen and Carbon dioxide. Oxygen is the gas needed for respiration and is transported to the body's cells. Carbon dioxide is the waste gas produced by respiration that must be carried away from the body's cells.
• The circulatory system carries two types of blood: Oxygen-rich blood and Oxygen-poor blood.
• Oxygen-rich blood - blood travelling to the body cells, high oxygen content, and low carbon dioxide content. Left side of the heart.
• Oxygen-poor blood: blood from the heart, low oxygen content, high carbon dioxide content. Right side of the heart.
• It takes about 30 seconds for blood to go once around the body.
• The left side of the heart pumps oxygen-rich blood to the rest of the body/body cells.
• The right side of the heart pumps oxygen-poor blood to the lungs.
• Circulatory System cycle

  A) lungs

  B) body's cells

  
• Muscle tissue - the heart is made out of muscle that keeps pumping blood around the body.

  A) Muscle tissue

  
• The blood vessels on the outside of the heart carry

  oxygen-rich blood to the heart muscle cells. Oxygen-poor blood is then carried away from these cells by outer blood vessels and back into the heart.

  A) Blood vessels

  
• The heart is divided into two sides to separate oxygen-rich and oxygen-poor blood.

  A) Left side of the heart, oxygen-rich blood

  B) Right side of the heart, oxygen-poor blood

  
• Chambers of the heart

  A) right atrium

  B) right ventricle

  C) left atrium

  D) left ventricle

  
• Different functions of each chamber.

  A) blood to the lungs

  B) blood from the body

  C) blood to the body

  D) blood from the lungs

  
• Valves - prevent blood from flowing in the wrong direction.
• The valves between the atria and ventricles are connected to the inner walls of the heart by tough tendons.
• The heart can pump blood because it is made of muscle. Muscle tissue works by contracting (squeezing) and relaxing.