B2: Organisation

• What is the difference between tissue, organ, and organ system?

  • Tissue: One type of cell performing a function
  • Organ: Multiple cell types working together
  • Organ System: Group of organs working together
• What are the main components of the digestive system?

  • Mouth: Mechanical breakdown of food
  • Salivary glands: Produce amylase
  • Liver: Produces bile
  • Gallbladder: Stores bile
  • Small intestine: Absorbs nutrients
  • Stomach: Digests food
  • Pancreas: Produces enzymes
  • Large intestine: Removes excess water
  • Rectum/Anus: Excretes waste
• What does lipase do?

  Breaks down fats into fatty acids
• What does protease do?

  Breaks down proteins into amino acids
• What does amylase do?

  Breaks down starch into sugars
• How do enzymes work?

  • Enzymes have a specific active site
  • Substrates fit into the active site
  • Enzyme-substrate complex forms
  • Enzyme releases products unchanged
• How does temperature affect enzyme activity?

  Enzymes denature at high temperatures
• What is the optimal temperature for enzyme activity?

  The temperature at which enzymes function best
• How does pH affect enzyme activity?

  Extreme pH levels denature enzymes
• What is the structure of the respiratory system?

  • Air enters through mouth/nose
  • Travels down trachea (windpipe)
  • Branches into bronchi and bronchioles
  • Gas exchange occurs in alveoli
  • Diaphragm aids in breathing
• What is the structure of the cardiovascular system?

  • Blood pumped from heart to lungs
  • Returns to heart, then to body
  • Path: Vena cava → Right atrium → Right ventricle → Pulmonary artery → Pulmonary vein → Left atrium → Left ventricle → Aorta
• What is the function of heart valves?

  Prevent backflow of blood
• Why do arteries have thick walls?

  To withstand high pressure of blood
• What is the function of capillaries?

  Facilitate diffusion of substances
• What is the main function of veins?

  Carry deoxygenated blood back to heart
• What is the color of blood due to?

  Red blood cells without nuclei
• What happens during cardiovascular disease?

  Fatty deposits build up in arteries
• What can lead to a heart attack?

  Blocked arteries restricting oxygen supply
• What are risk factors for cardiovascular disease?

  Smoking, high blood pressure, high salt/fat diet
• What is the role of the diaphragm in respiration?

  Helps bring air in and out
• What is the role of intercostal muscles?

  Allow rib cage to expand
• What is the function of the liver in digestion?

  Produces bile to emulsify fats
• What does the gallbladder do?

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

  Absorbs nutrients into the blood
• What is the function of the large intestine?

  Removes excess water from waste
• What is the role of the rectum/anus?

  Excretes waste from the body
• How do enzymes work with the lock and key mechanism?

  Substrates fit into specific active sites
• What happens to enzymes at high temperatures?

  They become denatured and lose function
• What is the optimal pH for enzyme activity?

  The pH at which enzymes work best
• What is the role of the alveoli in the respiratory system?

  Site of gas exchange in lungs
• What is the function of the heart?

  Pumps blood around the body
• What is the pathway of blood through the heart?

  Vena cava → Right atrium → Right ventricle → Pulmonary artery → Pulmonary vein → Left atrium → Left ventricle → Aorta
• What is the difference between oxygenated and deoxygenated blood?

  Oxygenated blood carries oxygen; deoxygenated does not
• What is the role of pacemakers in the heart?

  Help regulate heart rhythm
• What happens to blood pressure in arteries?

  Blood pressure is high due to pumping
• What color do red blood cells give blood?

  Red
• Why do red blood cells lack nuclei?

  To have more space for oxygen
• What is the main function of red blood cells?

  Carrying oxygen
• What are white blood cells part of?

  The immune system
• What are platelets important for?

  Clotting blood