Blood

• What are the main components of blood?

  Plasma, red blood cells, white blood cells, and platelets
• What is the primary function of plasma in blood?

  To transport useful substances and waste around the body
• What type of molecules does plasma transport?

  Digested food molecules and waste substances
• What waste substances are transported by plasma?

  Urea and carbon dioxide
• What is the main function of red blood cells?

  To transport oxygen to cells around the body
• What molecule do red blood cells contain that holds oxygen?

  Haemoglobin
• Why do red blood cells have no nucleus?

  To allow more room to carry oxygen
• What shape do red blood cells have and why?

  Concave disc shape, giving them a large surface area
• What is the role of white blood cells?

  To fight infections as part of the immune system
• What feature do white blood cells have that red blood cells do not?

  They have a nucleus
• How do some white blood cells help fight infections?

  By producing antibodies and engulfing pathogens
• What do some white blood cells produce to neutralize toxins?

  Antitoxins
• What is the function of platelets in blood?

  To help form blood clots at the site of a wound
• What allows platelets to stick together?

  Proteins that cover them
• Where do platelets stick to help with clotting?

  To damaged areas of blood vessels
• Do platelets have a nucleus?

  No