blood

• what a red blood cell‘s job?

  to carry oxygen from the lungs to all the cells in the body.
• what shape are red blood cells?

  biconcave disc shape
• why do red blood cells have a biconcave disc shape?

  to give a large surface area for absorbing oxygen.
• why do red blood cells not have a nucleus?

  allows more room to carry oxygen.
• what do red blood cells contain that makes them red?

  a red pigment called haemoglobin, which contains iron.
• what does haemoglobin do in the lungs?

  haemoglobin binds to oxygen to become oxyhaemoglobin. In body tissues, the reverse happens, oxyhaemoglobin splits up into haemoglobin and oxygen, to release oxygen to the cells.
• what are phagocytes?

  white blood cells that can change shape to engulf unwelcome microorganism, this is called phagocytosis.
• what are lymphocytes?

  white blood cells that produce antibodies against microorganisms. Some produce antitoxins to neutralise any toxins produced by the microorganisms.
• what do your white blood cells do when you have an infection?

  your white blood cells multiply to fight it off, so a blood test will show a high white blood cell count.
• what do white blood cells have that red blood cells dont?

  Nucleus
• what are platelets?

  small fragments of cells. They have no nucleus.
• what is the purpose of platelets?

  they help the blood clot at a wound, to stop all your blood pouring out and to stop microorganisms getting in.
• what happens if there is a lack of platelets?

  can cause excessive bleeding and bruising.
• What is plasma?

  a pale straw coloured liquid which carries just about everything.
• What does plasma contain?

  • red and white blood cells and platelets
  • nutrients like glucose and amino acids
  • carbon dioxide from the organs to the lungs
  • urea from the liver to the kidneys
  • hormones
  • proteins
  • antibodiesbams antitoxins produced by white blood cells
• what are the nutrients that are carried in plasma?

  glucose and amino acids. these are soluble products of digestion which are absorbed from the gut and taken to the cells of the body.
• what 3 things are suspended in blood plasma?

  • red blood cells
  • platelets
  • white blood cells
• what are the 2 types of white blood cells?

  phagocytes and lymphocytes
• what are platelets responsible for?

  triggering blood clotting at the sites of wounds.
• what are platelets?

  small cell fragments that do not have a nucleus.
• what are red blood cells called?

  erythrocytes
• what is blood?

  a tissue which means it is a group of similar cells that act harmoniously to perform a similar function.
• why are red blood cells small?

  so they can pass through tiny capillaries.
• white blood cells do have a nucleus.
• why can white blood cells change shape?

  it allows them to squeeze through the walls of blood vessels into body tissues and to engulf harmful microorganisms.
• what are white blood cells responsible for?

  defence against infection.
• What do red blood cells contain that binds with oxygen in the lungs?

  haemoglobin