Additional Knowledge

• the human body

  a complex organism, needs very highly organized systems to function simultaneously
• circulatory system

  transport system of the body
• blood vessels

  pathways/tubes through which blood flows
• three kinds of blood vessels

  1. arteries
  2. veins
  3. capillaries
• arteries

  carry blood away from heart
• veins

  carry blood back to the heart
• capillaries

  carry blood rich in oxygen to the tissue to carry away waste products
• blood

  the carrier of food and gases that are trasported to and from the body cells
• circulation

  process which food and gases are transported throughout the body
• circulatory system

  continuous travel of the blood flow from the heart to the different body cells and back to the heart
• vena cava

  carries blood "from the body cells"
• pulmonary artery

  carries blood to the lungs
• aorta:

  • the main artery of the body, supplying oxygenated blood to the circulatory system.
  • it passes over the heart from the left ventricle and runs down in front of the backbone.
  • carries blood to the body's cells
• pulmonary veins

  carry deoxygenated blood from the lungs to the left atrium
• heart

  a hallow organ,which is made up of special muscle tissues
• pericardium

  surrounded heart by a double-walled sac
• heart two chambers

  1. atrium/atria ( upper chamber)
  2. ventricle (lower chamber)
• septum

  - prevents mixing of blood in the heart

  • a wall separates the right and left chambers
• ventricles

  pump the blood that carries nutrients to all parts of the body
• valves

  • between the atria and ventricles
  • allow the blood to flow in one direction
  • stops the blood from flowing back to the atria
• right atrium

  • receives deoxygenated blood from the body
• left atrium - receives blood from the left ventricle and pumps it to the left ventricle
• atria

  receiving chambers of the heart
• ventricles

  the pumping chambers of the heart
• left atrium

  oxygenated blood flows from the lungs
• systole

  heartbeat consists of a contractions of the heart

  
  

  diastole

  relaxation of heartbeat
• blood vessels

  blood flows through tubes
• Arteries

  carries blood directly from the heart to all parts of the body
• capillaries

  connect the arteries and the veins
• veins

  carry blood back to the heart
• Blood vessels


  Tubes that blood flows through - arteries, capillaries, veins
• Arteries


  • Carry blood directly from the heart to all parts of the body
  • Elastic and tough thick vessels with three coat walls
  • Allow expansion and contraction
  • Blood is bright red - combination of red blood cells and oxygen
  • Aorta is the largest artery found in the heart
  • Branch out into smaller tubes called arterioles, which also branch out into capillaries
• Capillaries


  • Tiny blood vessels that connect the arteries and veins
  • Longer than all the arteries and veins joined together
  • Thin-walled vessels
  • Where actual exchange of food and waste products takes place
• Veins


  • Carry blood-containing carbon dioxide or deoxygenated blood from the cells back to the heart
  • Thin-walled with fibers of the connective tissues
  • Closer to the skin, appear bluish in color
  • Have valves that stop the blood from flowing backward
• The blood is called the red river of life
• Blood


  Liquid that contains red blood cells, white blood cells and platelets<|>Plasma is the liquid part, made up of 90% water with dissolved materials like digested food and waste
• Red blood cells (RBC)

  • Also called erythrocytes
  • Produced in the red bone marrow
  • Contain hemoglobin, the red pigment of the blood
  • Carry oxygen to the lungs and to the cells of the body
• White blood cells (WBC)


  • Also called leucocytes
  • Serve as antibodies, fight infections and attack/destroy disease-carrying organisms
  • Larger and fewer than red blood cells - about 500 RBC for every 1 WBC
• Platelets


  • Also called thrombocytes
  • Help make the blood clot or stop bleeding when a part of the body is cut or wounded
  • Stick to the walls of the broken vessel like a tangled network of fine threads to close the vessel walls and stop bleeding
• Average amount of blood in an adult male is 5.4 million red blood cells per cubic millimeter, and in an adult female is 4.8 million per cubic millimeter