Chapter 2 - Animal tissues, organs and organ systems

• What is meant by a tissue?

  A group of cells with similar structure
• What is an organ?

  A group of tissues working together
• What is an organ system?

  A group of organs working together
• What is the main function of muscle cells?

  To contract and get shorter
• Why do muscle cells contain many mitochondria?

  To provide energy needed for contraction
• What is the definition of a tissue?

  A group of cells with similar structure and function
• What types of tissues does the stomach contain?

  Muscle tissue and glandular tissue
• What is the function of glandular tissue in the stomach?

  To release enzymes
• What are the three main nutrients found in food?

  Carbohydrates, proteins, and lipids
• Why must large food molecules be digested?

  They are too large to be absorbed
• What role do enzymes play in digestion?

  They break down large molecules into small ones
• What begins the digestion of starch?

  Enzymes in saliva
• What is the function of hydrochloric acid in the stomach?

  To help enzymes digest proteins
• What is the role of the pancreas in digestion?

  It releases enzymes for digestion
• What does bile do in the digestive process?

  Speeds up digestion of lipids
• How are small food molecules absorbed in the small intestine?

  By diffusion or active transport
• What is released from the body at the end of digestion?

  Feces
• What are the products of digestion used for in the body?

  To build new carbohydrates, lipids, and proteins
• What is glucose used for in the body?

  In respiration
• What are the main functions of the organs in the digestive system?

  • Mouth: Chews food and begins starch digestion
  • Stomach: Digests proteins and churns food
  • Small intestine: Continues digestion and absorbs nutrients
  • Large intestine: Absorbs water and releases feces
• What is the process of digestion in the digestive system?

  1. Large food molecules are broken down by enzymes.
  2. Small molecules are absorbed into the bloodstream.
  3. Nutrients are used to build carbohydrates, lipids, and proteins.
  4. Glucose is utilized in respiration.
• What should you be able to describe by the end of the video?

  Enzymes in the digestive system
• What is the role of enzymes in digestion?

  They catalyze chemical reactions and speed them up
• What are enzymes made of?

  Large protein molecules
• What is the active site of an enzyme?

  It is where the substrate attaches
• What is the substrate in enzyme reactions?

  The molecule that the enzyme breaks down
• What does the lock and key theory describe?

  Enzymes are specific to their substrates
• What type of enzymes break down proteins?

  Proteases
• Where are proteases found in the body?

  In the stomach and pancreatic fluid
• What are proteins made of?

  Amino acids
• What happens to proteins during digestion?

  They are converted back to amino acids
• What type of enzymes break down carbohydrates?

  Carbohydrases
• What is the specific enzyme that breaks down starch?

  Amylase
• Where is amylase found?

  In saliva and pancreatic fluid
• What is the structure of a lipid molecule?

  Glycerol and three fatty acids
• What enzyme digests lipids?

  Lipase
• What does lipase produce when it digests lipids?

  Glycerol and fatty acids
• Where is lipase found?

  In pancreatic fluid and small intestine
• What is the role of bile in lipid digestion?

  It emulsifies lipids to increase surface area
• Where is bile produced and stored?

  Produced in the liver, stored in gallbladder