B2

• What is a cell?

  A basic building block that all living organisms have.
• What is the role of enzymes?

  Enzymes catalyse (speed up) chemical reactions.
• Why does each enzyme only catalyse one specific reaction?

  Because of the unique shape of its active site.
• What is a tissue?

  A group of similar cells that work together.
• What is an organ?

  A group of different tissues that work together.
• What is an organ system?

  A group of organs working together.
• How do enzymes and substrates interact?

  Enzyme and substrate fit together like a lock and key.
• What happens to enzymes at high temperatures and extreme pH levels?

  They change shape and no longer work.
• What do digestive enzymes do?

  They break BIG molecules down into smaller, soluble ones.
• What are the products of digestion used for?

  • To make new carbohydrates
  • To make new proteins
  • To make new lipids
• What does amylase break down?

  Starch into maltose and other sugars.
• Where is amylase produced?

  In the salivary glands, small intestine, and pancreas.
• What does protease break down?

  Protein into amino acids.
• Where is protease produced?

  In the stomach, small intestine, and pancreas.
• What does lipase break down?

  Lipid into glycerol and fatty acids.
• Where is lipase produced?

  In the small intestine and pancreas.
• How does bile aid digestion?

  1. Makes conditions alkaline for better enzyme function.
  2. Emulsifies fat for a larger surface area for lipase.
• Where is bile made and stored?

  Bile is made in the liver and stored in the gall bladder.
• What is the function of the trachea?

  It is a passage for air to enter and exit the lungs.
• What are alveoli?

  They are tiny air sacs in the lungs surrounded by capillaries.
• What occurs during gas exchange in the alveoli?

  Gases diffuse between the alveolus and the blood.
• What is the circulatory system made up of?

  The heart, blood vessels, and blood.
• What type of circulatory system do humans have?

  Humans have a double circulatory system.
• What are the two circuits in the human circulatory system?

  1. Heart (right ventricle) → lungs → heart
  2. Heart (left ventricle) → rest of body → heart
• What controls the resting heart rate?

  "Pacemaker" cells in the right atrium wall.
• What is an artificial pacemaker?

  An electrical device put under the skin to control heartbeat.
• What do coronary arteries supply?

  Oxygenated blood to the heart muscle.
• What are the three types of blood vessels?

  1. Arteries - carry blood away from the heart.
  2. Capillaries - exchange substances with body cells.
  3. Veins - carry blood back to the heart.
• What is the function of red blood cells?

  To carry oxygen around the body.
• What is the function of white blood cells?

  To defend against infection.
• What is the function of platelets?

  To help blood to clot at a wound.
• What is the function of plasma?

  To carry everything in the blood.
• What is coronary heart disease?

  A disease where blood flow is restricted due to fatty deposits in coronary arteries.
• What are five treatments for cardiovascular disease?

  1. Statins
  2. Stent
  3. Heart transplant
  4. Artificial heart
  5. Replacement heart valves
• What is the advantage of statins?

  They reduce the amount of LDL cholesterol in the blood.
• What is a disadvantage of statins?

  They need to be taken long-term and can have side effects.
• What is the advantage of a stent?

  It keeps coronary arteries open for a long time.
• What is a disadvantage of a stent?

  Surgery can cause bleeding and infection.
• What is the advantage of a heart transplant?

  It can treat heart failure effectively.
• What is a disadvantage of a heart transplant?

  Donor hearts can be rejected by the immune system.