the heart and blood vessels

• Blood is transported in arteries, veins and capillaries.
• Blood is pumped from the heart in the arteries. It is returned to the heart in the veins.
• Arteries carry oxygenated blood away from the heart

  A) artery

  B) vein

  C) tissue

  D) lumen

  
• labelllll

  A) away

  B) to

  C) oxygenated

  D) deoxygenated

  E) high

  F) low

  G) thick

  H) thin

  I) connective

  J) narrow

  K) wide

  
• Capillaries connect the smallest branches of arteries and veins
• The walls of capillaries are just one cell thick.
• • Oxygen diffuses through the capillary wall, into the tissue fluid, and the cells.
• • Carbon dioxide diffuses from the cells into the tissue fluid, then across the capillary walls into the blood plasma.
• • Glucose diffuses from the blood plasma, across the capillary walls to the tissue fluid, and then to the cells.
• • The waste product urea diffuses from the cells of the liver, to the tissue fluid, and then across the capillary walls into the blood plasma.
• heart

  A) right

  B) left

  C) pulmonary

  D) aorta

  E) vena cava

  F) pulmonary

  G) atrium

  H) atrium

  I) valve

  J) ventricle

  K) ventricle

  
• The heart has four chambers - two atria and two ventricles.
•  Blood is prevented from flowing back into the atria by heart valves.
• blood enters the heart through the atria. 
• Blood leaves the heart in the aorta and the pulmonary artery
• Humans have a double circulatory system.
• the heart pumps blood through the pulmonary circuit and the systematic circuit.
• The pulmonary circulation transports blood to the lungs.
• At the lungs:

  • oxygen diffuses into the blood from the alveoli - the blood becomes oxygenated
  • carbon dioxide diffuses from the blood into the lungs
• he systemic circulation transports:

  • oxygen and nutrients to the body
  • carbon dioxide and other wastes away from cells
• The pulmonary circulation is under lower pressure, because:

  • blood is delivered to the lungs only, which are very close to the heart
  • in a healthy person, this lower pressure is optimum for the diffusion of gases
• Blood passes through the heart twice in one complete circulation of the body.
• can you hear the silence... can you see the dark... can you fix the broken... CAN YOU FEEL MY HEARTTTTT (for the arrows say downwards or upwards)

  A) vena cava

  B) vena cava

  C) right atrium

  D) upwards

  E) downwards

  
• labelle

  A) head

  B) aorta

  C) small

  D) lungs

  E) vena cava

  F) pulmonary

  G) pulmonary

  
• Blood must flow one way only through the circulatory system. Valves in the heart, aorta and veins ensure this one-way flow. Closure of a valve prevents backflow.
• If heart valves become faulty, you can replace them with biological or mechanical valves. Mechanical valves last longer but it may be possible for blood clots to occur.
• Specialised cells in the right atrium generate electrical signals that make the heart contract independently of the nervous system. These specialised cells act as a natural pacemaker.
• An artificial pacemaker is a small, battery-operated electronic device implanted in a person's chest that sends out regular, adjustable electrical impulses to produce normal contractions of the heart.
• Blood components consist of: white blood cells, red blood cells, plasma, and platelets.
• wtf is a platelet

  A) carbon

  B) digested

  C) oxygen

  D) pathogens

  E) antibodies

  
• (true or false) Red blood cells don't have a nucleus

  True
• Haemoglobin and oxygen produce oxyhaemoglobin
• Red blood cells are small and flexible, si they can fit through narrow blood capillaries.
• Capillaries carry blood that is returning from the rest of the body, meaning it has a higher concentration of carbon dioxide than the lungs. The carbon dioxide diffuses into the alveoli, where there is a lower concentration, to be breathed out.
• The capillary picks up oxygen from the alveoli, which contain a higher concentration of oxygen than in the blood. Oxygen diffuses from the alveoli into the blood, where there is a lower concentration to be carried to the body cells
• The circulatory system consists of two circuits joined together. The first one pumps deoxygenated blood to the lungs and returns deoxygenated blood to the heart. The second one pumps oxygenated blood to all other organs and returns deoxygenated blood to the heart.
• red blood cells have a biconcave disc shape
• Platelets are small fragments of blood with no nucleus. They help the blood to clot at a wound.