B3

• What is the basic unit of life?

  Cell
• What is a tissue?

  A group of similar cells working together
• What is an organ?

  A structure made of different tissues
• What is an organ system?

  A group of organs working together
• What is an organism?

  A living being made of organ systems
• What is the primary function of the digestive system?

  To break down food into smaller molecules
• What is the first organ in the digestive system?

  Mouth
• What role do teeth play in digestion?

  They break down food physically
• What enzyme in saliva starts carbohydrate digestion?

  Amylase
• What is the function of the oesophagus?

  Moves food from mouth to stomach
• What is peristalsis?

  Muscle contractions that move food
• What does the stomach secrete?

  Gastric juices including hydrochloric acid
• What is the main site of digestion and nutrient absorption?

  Small intestine
• What increases the surface area for absorption in the small intestine?

  Villi
• What is the duodenum?

  The first part of the small intestine
• What is the function of the ileum?

  Absorbs nutrients into the bloodstream
• What does the liver produce?

  Bile
• What does the gall bladder do?

  Stores bile produced by the liver
• What is the role of bile?

  Emulsifies fats to increase surface area
• What does the pancreas produce?

  Digestive enzymes like amylase
• What is the function of the large intestine?

  Absorbs water and salts, forms feces
• What are enzymes?

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

  Carbohydrates into simple sugars
• Where is protease found?

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

  Lipids into fatty acids and glycerol
• What are optimum conditions for enzymes?

  Specific temperature and pH for activity
• What pH does amylase work best at?

  Neutral pH around 7
• What pH does pepsin work best at?

  Acidic pH around 2
• What pH does lipase work best at?

  Neutral pH in the small intestine
• What is mechanical digestion?

  Physical breakdown of food into smaller pieces
• What is chemical digestion?

  Breakdown of food by enzymes into simpler molecules
• What are villi?

  Tiny projections in the small intestine
• How do villi aid in absorption?

  Increase surface area for nutrient absorption
• What is the role of bile in the digestive process?

  Emulsifies fats and neutralizes stomach acid
• How does dietary fiber affect digestion?

  Promotes peristalsis and prevents constipation
• What is lactose intolerance?

  Deficiency in the enzyme to digest lactose
• How can obesity affect digestion?

  Poor diet can lead to malnutrition
• How are absorbed nutrients transported in the body?

  Through capillaries in the villi to bloodstream
• What happens to glucose after absorption?

  Transported to cells for energy
• What are amino acids used for in the body?

  To build proteins