Organisation Biology

• What is an enzyme?

  A biological catalyst with an active site
• What is the role of the small intestine?

  To absorb nutrients
• How do we test a food sample for sugars?

  Add Benedict's reagent and heat
• What is the symbol equation for photosynthesis?

  6CO2+ 6H2O → C6H12O6+ 6O2
• What is a tissue?

  A group of similar cells working together
• What are the four main components of blood?

  Plasma, RBCs, WBCs, platelets
• Why is blood classed as a tissue?

  It consists of similar cells working together
• What is the function of red blood cells?

  Carry Oxygen around the body
• How are red blood cells adapted for their function?

  No nucleus, disc shape, contains hemoglobin
• What is the function of white blood cells?

  Fight infection
• How are white blood cells adapted for their function?

  Change shape to engulf pathogens
• What is the function of platelets?

  Form blood clots at wounds
• How are platelets adapted for their function?

  Plug cuts with a network of fibers
• What is the function of plasma?

  Transport medium for nutrients and waste
• What does lipase do?

  Breaks down lipids into fatty acids and glycerol
• What is a stem cell?

  An undifferentiated cell
• What are the three main types of blood vessels in animals?

  Arteries, veins, capillaries
• How do veins keep blood moving in the right direction?

  They have valves to prevent backflow
• How are capillaries adapted to their function?

  Walls are one cell thick for diffusion
• Why does blood spurt out when an artery is cut?

  High pressure blood due to small lumen
• What is the function of the aorta?

  Main blood vessel out of the heart
• What is the function of the vena cava?

  Returns blood to the heart
• What is the function of the pulmonary artery?

  Returns blood to the lungs
• What is the function of the pulmonary vein?

  Returns blood from the lungs to the heart
• What is a double circulatory system?

  Blood goes through the heart twice per circuit
• Why do humans need a double circulatory system?

  To efficiently deliver oxygen and nutrients
• What is the role of the pacemaker in the heart?

  Controls the resting heart rate
• What is coronary heart disease (CHD)?

  Fatty material builds up in coronary arteries
• Why is coronary heart disease serious?

  Reduces blood flow and oxygen to heart cells
• What is a stent and how does it help?

  A wire mesh to hold open coronary arteries
• Why are faulty valves a problem?

  Prevent effective blood flow through the heart
• What is heart failure?

  A condition where the heart cannot pump effectively
• What is an artificial heart?

  A temporary solution until a donor heart is available
• What is an artificial pacemaker?

  An electrical device to correct heart rate irregularities
• What are the advantages of heart transplants?

  Allows decent quality of life post-surgery
• What are the disadvantages of heart transplants?

  Risk of rejection and infection post-surgery
• What are the advantages of using stents?

  High success rate and lower risk of heart attack
• What are the disadvantages of using stents?

  Risk of bleeding and infection
• What are the advantages of statins?

  Good reduction in deaths from heart disease
• What are the disadvantages of statins?

  Side effects and long-term use required