Animal

• What is the main function of the digestive system?

  To digest food and absorb nutrients
• What do the pancreas and salivary gland produce?

  Digestive juices containing enzymes
• What is the role of the stomach in digestion?

  Produces hydrochloric acid to kill bacteria
• What is the role of the small intestine?

  Site where soluble food molecules are absorbed
• What does the liver produce in digestion?

  Bile, which emulsifies lipids
• What is the role of the large intestine?

  Absorbs water from undigested food
• What is the role of enzymes in digestion?

  Speed up the breakdown of food
• How does the shape of an enzyme affect its function?

  Enzymes have a specific active site for substrates
• What is metabolism?

  The sum of all reactions in a cell
• What types of reactions do enzymes catalyse?

  Building, changing, and breaking down molecules
• What is the lock and key hypothesis?

  Enzyme active site and substrate are complementary
• How does temperature affect enzyme action?

  Increases action until denaturation occurs
• What is the optimum temperature for enzymes?

  Around 37°C
• How does pH affect enzyme function?

  Extreme pH alters the active site shape
• Where are carbohydrases produced?

  Salivary gland and pancreas
• What is the role of carbohydrases?

  Break down carbohydrates into sugars
• What is the role of proteases?

  Break down proteins into amino acids
• What is the role of lipases?

  Break down lipids into fatty acids
• How are the products of digestion used?

  To build larger molecules like proteins
• Where is bile made and stored?

  Made by the liver, stored in gallbladder
• What is the role of bile?

  Neutralizes stomach acid and emulsifies lipids
• What is the heart?

  An organ that pumps blood around the body
• What is the purpose of the circulatory system?

  Carries oxygen and removes waste substances
• How does the double circulatory system work?

  One pathway to lungs, one to tissues
• Where does blood from the right ventricle go?

  To the lungs
• Where does blood from the left ventricle go?

  To body tissues
• Why is the double circulatory system important?

  It allows higher pressure for oxygenated blood
• How many chambers does the heart have?

  Four chambers
• What are the names of the heart chambers?

  Right atrium, right ventricle, left atrium, left ventricle
• Why is the left ventricle wall thicker?

  It pumps blood at higher pressure
• What are the four main blood vessels associated with the heart?

  Aorta, pulmonary vein, vena cava, pulmonary artery
• What is the purpose of valves in the heart?

  Prevent the backflow of blood
• What is the purpose of coronary arteries?

  Supply the heart muscle with oxygenated blood
• Describe the process of blood flow through the heart.

  • In: Blood enters right atrium via vena cava
  • Down: Blood enters left atrium via pulmonary vein
  • Close: Valves close to prevent backflow
  • Contract: Atria contract, forcing blood into ventricles
• What is the approximate value of the natural resting heart rate?

  70 beats per minute
• How is the heart rate controlled?

  By a group of cells in the right atrium
• How can an abnormal heart rhythm be treated?

  Using an artificial pacemaker
• What are the three types of blood vessel in the body?

  • Arteries
  • Veins
  • Capillaries
• How are arteries adapted for their function?

  • Carry blood away from the heart
  • Thick muscle layer for strength
  • Thick elastic layer for stretching
• How are veins adapted for their function?

  • Carry blood towards the heart
  • Wide lumen for low pressure
  • Valves to prevent backflow