The blood

• What is blood classified as?

  A tissue
• What is the primary function of blood?

  To transport substances around the body
• What are the main components of blood?

  Red blood cells, white blood cells, platelets, plasma
• What is the shape of red blood cells?

  Biconcave shape
• Why do red blood cells have a biconcave shape?

  To provide a large surface area for oxygen absorption
• What pigment do red blood cells contain?

  Haemoglobin
• What is the role of haemoglobin in red blood cells?

  To carry oxygen
• How do red blood cells differ from most animal cells?

  They lack a nucleus
• What process do body cells use oxygen for?

  Respiration
• How does oxygen enter the blood from the lungs?

  Through diffusion
• What happens to oxygen in the lungs?

  It combines with haemoglobin to form oxyhaemoglobin
• What occurs in body tissues regarding oxyhaemoglobin?

  It splits into haemoglobin and oxygen
• What is the function of white blood cells?

  To defend against microorganisms
• How do white blood cells defend against microorganisms?

  By engulfing, producing antibodies, and antitoxins
• What is the process called when white blood cells engulf microorganisms?

  Phagocytosis
• What are platelets?

  Small fragments of cells
• What is the role of platelets in the blood?

  To help blood clot at wounds
• What happens when there is a lack of platelets?

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

  A pale straw-coloured liquid in blood
• What does plasma carry in the blood?

  Red and white blood cells, nutrients, hormones
• What nutrients does plasma carry?

  Glucose and amino acids
• What waste product does plasma transport from the liver?

  Urea
• What do antibodies and antitoxins do?

  Neutralise toxins and fight infections
• What are the main functions of blood components?

  • Red blood cells: Transport oxygen
  • White blood cells: Defend against disease
  • Platelets: Help blood clot
  • Plasma: Carry nutrients and waste
• What are the differences between red and white blood cells?

  • Red blood cells: No nucleus, transport oxygen
  • White blood cells: Have a nucleus, defend against disease
• What is the process of oxygen transport in the blood?

  1. Oxygen enters lungs
  2. Diffuses into blood
  3. Combines with haemoglobin to form oxyhaemoglobin
  4. Released to body tissues
• What are the roles of white blood cells in the immune response?

  • Engulf microorganisms (phagocytosis)
  • Produce antibodies
  • Produce antitoxins
• What does plasma transport in the body?

  • Red and white blood cells
  • Nutrients (glucose, amino acids)
  • Carbon dioxide
  • Urea
  • Hormones
  • Proteins
  • Antibodies and antitoxins