2nd yr biology🧫🧬🧪🔬

• Cell membrane


  Outer layer of a cell
• Nucleus


  Contains genetic material
• Nucleolus


  Structure within the nucleus
• Mitochondria


  Powerhouses of the cell
• Plant cell


  • Cell wall
  • Chloroplasts
  • Central vacuole
• Terms


  • nb
  • tocher
  • Tatetage
  • Dag
  • Awol
  • dagg
  • Breathing in
  • The Lungs
  • Breathing mechanism
  • Breathing
  • Summe
  • pay
  • A 02
  • 866
  • Copront
• Why is there cartilage in the walls of the trachea?
• Cartilage in trachea walls


  To help open
• Adaptations


  • alveslus
  • tiny blood vesse
  • direction of blood flow
• State three adaptations of the alveoli that make gas exchange more efficient.
• Alveoli adaptations


  • Large Surface area
  • Thin walls
  • Muscles contract to move the
• Breathing in


  1. Intercostal ribs and outwards

  2. Diaphragm contracts and moves downwards

  3. Volume inside the chest increases

  4. Pressure decreases

  5. Air rushes into lungs and they inflate
• Smoking is a carcinogen, what does this mean?
• Causes cancer
• Harmful chemicals in cigarette smoke

  • Carbon monoxide
  • Reduce O₂ in blood
• How mucus and cilia keep the lungs free of bacteria and dust particles

  1. Trap made in blood

  2. Cilia move mucus out of lung
• Aerobic respiration


  Respiration with oxygen
• Anaerobic respiration


  Respiration without oxygen
• Aerobic respiration


  1. Occurs in mitochondria

  2. Provides energy
• Importance of aerobic respiration

  • Provides energy for the body
• Respiration


  1. A-B: Sprint start

  2. B-C: Maintain pace

  3. C-D: Sprint finish

  4. D-E: Cool down and finish
• Equation for aerobic respiration

  Glucose + Oxygen -> Carbon dioxide + Water + ENERGY
• Importance of anaerobic respiration


  • Provides energy when oxygen is limited
• Oxygen debt


  Amount of oxygen required to break down lactic acid produced during anaerobic respiration
• When we exercise


  We need more energy for our muscles to contract
• Needing more energy when exercising


  Requires more respiration
• More respiration when exercising


  Leads to breathing more to get more oxygen
• Anaerobic respiration


  Can cause lactic acid buildup
• Composition of inhaled air

  • Oxygen
  • Carbon dioxide
• Composition of exhaled air

  • Oxygen (less)
  • Carbon dioxide (more)
  • Water
  • Lactic acid
• Main food groups


  • Carbohydrates
  • Protein
  • Fat
  • Fibre
  • Vitamins
  • Minerals
  • Water
• Balanced diet


  A diet that includes all the main food groups
• We need all the main food groups in our diet for it to be described as a balanced diet
• Carbohydrates provide energy
• Protein is required for cell growth and repair
• Fat is stored as a reserve energy source
• Fibre helps with digestion and insulation from the cold
• Vitamins and minerals are required to maintain health (e.g. calcium for bones, iron for blood)
• Water is essential to prevent dehydration
• People have different energy requirements based on their body and activities