The Heart and Blood

• Label the Diagram

  A) Pulmonary Artery

  B) Aorta

  C) Pulmonary Vein

  D) Left Atrium

  E) Left Ventricle

  F) Vena Cava

  G) Right Atrium

  H) Right Ventricle

  
• Deoxygenated blood enters the heart through the vena cava and goes into the right atrium. It then enters the right ventricle and moves to the lungs through the pulmonary artery where it is oxygenated.
• Oxygenated blood moves from the lungs back into the heart through the pulmonary vein. It enters the left atrium and then the left ventricle before being pumped to the rest of the body through the aorta.
• The left side of the heart is thicker because it has to pump blood further.
• The rules for labelling a diagram of a heart:

  R-VAVA lungs VAVA-L

  a comes before v in the alphabet

  artery - a for away

  vein - in for in

  you are looking at someone else
• The pacemaker is located in the right atrium.
• The Blood Pathway:

  Heart

  Artery

  Capillary

  Vein
• Arteries take blood away from the heart (a for away). They have elastic walls, thick, elastic, muscular tissue and a small lumen. Arteries are more muscular and have a pulse. They carry bright red blood and high pressures. Coronary arteries supply blood to the heart muscle.
• Veins carry blood into the heart. They have a large lumen and thin muscular elastic tissue. Veins will collapse if empty. They contain valves to prevent backflow and blood moves through them at low pressures.
• Deteriorated valves are known as varicose.
• Capillaries are one cell thick and have thin walls to allow for quick diffusion. The walls are also permeable. Capillaries are small to reach every cell in the body and form a dense network around alveoli. Waste products pass into the blood through capillary walls. Capillaries have a very narrow lumen and connect arteries and veins.
• Blood is a tissue made up of 4 main components.
• Blood is part of the circulatory system.
• Red blood cells give oxygen to cells for respiration and makes up 45% of the blood in the human body. They contain no nucleus and a large surface area to allow space for haemoglobin. Haemoglobin latches onto oxygen molecules to transport them throughout the body.
• Platelets contain proteins that stick to each other in order to help wounds heal. They make up less than 1% of the blood. Platelets are small fragments of cells which contain no nucleus and help blood to clot.
• White blood cells help the body to defend against microorganisms that cause disease. They make up less than 1% of blood. White blood cells have a fluid cell membrane to help engulf microorganisms during phagocytosis and many ribosomes. These ribosomes help to produce antibodies and antitoxins.
• Plasma makes up 55% of blood and its function is to carry everything and transport substances. It contains dissolved substances and carries all other components of blood.
• The heart is a double circulatory pump because it is split in half and both sides pump blood to different areas at the same time.
• The heart is an organ that pumps blood around the body in a double circulatory system.
• The right ventricle pumps blood to the lungs where gas exchange takes place.
• The left ventricle pumps blood around the rest of the body.
• The natural resting heart rate is controlled by a group of cells located in the right atrium that act as a pacemaker.
• Artificial pacemakers are electrical devices used to correct irregularities in the heart rate.
• The body contains three different types of blood vessel: • arteries • veins • capillaries.
• The Lungs:

  • trachea
  • bronchi
  • alveoli
  • capillary network surrounding the alveoli
• Blood is a tissue consisting of plasma, in which the red blood cells, white blood cells and platelets are suspended.