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• Where does mechanical and chemical digestion begin in the human body?

  Mouth
• What role does saliva play in digestion?

  Saliva contains amylase to start starch breakdown
• What acid does the stomach produce to aid digestion?

  Hydrochloric acid
• What is the function of protease in the stomach?

  To digest proteins
• What is the main site of nutrient absorption in the digestive system?

  Small Intestine
• How do villi contribute to nutrient absorption?

  They increase the surface area for absorption
• What is the primary function of the large intestine?

  To absorb water from undigested food
• What is the role of the liver in digestion?

  The liver produces bile, which emulsifies fats
• What does the pancreas secrete to aid digestion?

  Digestive enzymes
• What are enzymes in digestion?

  Biological catalysts that speed up chemical reactions
• What does amylase break down?

  Starch into sugars
• Where is amylase found?

  In saliva and the pancreas
• What does protease break down?

  Proteins into amino acids
• Where is protease found?

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

  Fats into fatty acids and glycerol
• Where is lipase found?

  In the pancreas and small intestine
• What is the function of bile in digestion?

  To neutralize stomach acid and emulsify fats
• What are the four chambers of the heart?

  Right atrium, left atrium, right ventricle, left ventricle
• What is the double circulatory system?

  A system consisting of pulmonary circulation and systemic circulation
• What do arteries do?

  Carry oxygenated blood away from the heart
• Why do arteries have thick, muscular walls?

  To withstand high pressure
• What do veins do?

  Carry deoxygenated blood toward the heart
• What is the function of valves in veins?

  To prevent backflow of blood
• What are capillaries?

  Tiny, thin-walled vessels that allow exchange with tissues
• What do red blood cells do?

  Transport oxygen to body cells using hemoglobin
• What is the role of white blood cells?

  Part of the immune system, fighting infections
• What do platelets do?

  Help in blood clotting
• What is plasma?

  The liquid part of blood that transports nutrients, hormones, and waste products
• What causes coronary heart disease?

  Build-up of fatty material in the coronary arteries
• What are some risk factors for coronary heart disease?

  Smoking, high-fat diet, lack of exercise, obesity, and genetic predisposition
• What are some treatments for coronary heart disease?

  Lifestyle changes, medications, stents, and coronary bypass surgery
• What are the main functions of the digestive system?

  • Mechanical and chemical digestion
  • Nutrient absorption
  • Water absorption
  • Production of digestive enzymes and bile
• What are the components of blood and their functions?

  • Red Blood Cells: Transport oxygen
  • White Blood Cells: Fight infections
  • Platelets: Help in blood clotting
  • Plasma: Transports nutrients, hormones, and waste
• What are the characteristics of arteries, veins, and capillaries?

  • Arteries: Thick, muscular walls; carry oxygenated blood
  • Veins: Thinner walls; carry deoxygenated blood; have valves
  • Capillaries: Tiny, thin-walled; allow exchange with tissues