Biology

• What is diffusion?


  The movement of molecules from high to low concentration.
• What is osmosis?


  The movement of water molecules from a dilute to a concentrated solution across a partially permeable membrane.
• What is active transport?

  The movement of molecules/ions from a low to high concentration across a partially permeable membrane.
• What is the process called when we breathe in oxygen and breathe out carbon dioxide?


  This process is called gas exchange.
• What protects the lungs?

  The ribs, which are hard and strong bones that make up the ribcage.
• What gases are exchanged during respiration?

  Oxygen and carbon dioxide.
• What happens to carbon dioxide during respiration?


  It is produced and needs to be removed from the body.
• What is the equation for aerobic respiration?

  Glucose + Oxygen → Carbon Dioxide + Water (+ Energy).
• What is the role of the diaphragm during breathing?

  The diaphragm contracts and moves down to increase the volume of the thoracic cavity.
• How does the structure of the trachea facilitate its function?

  The trachea is a large tube that allows air to move easily to the lungs.
• What is the function of the alveoli?


  They are tiny air sacs where gas exchange occurs.
• How does air flow into the lungs?

  Air enters the body through the nose and mouth, then moves down the trachea, bronchi, bronchioles, and into the alveoli.
• What are the tasks related to the breathing system in the classroom?

  • Task A: Copy and match up the parts of the breathing system to their functions.
  • Task B: Glue in and label the parts of the breathing system.
  • Task C: Describe the order of structure that oxygen travels through to reach the blood.
  • Challenge: Explain how the actions of the ribcage, intercostal muscles, and diaphragm cause you to inhale.
• What is the first step in the pathway of oxygen to the blood?

  Oxygen is inhaled through the nose or mouth.
• What happens to oxygen after it travels down the trachea?

  It travels down the bronchi to go to each lung.
• What is the role of the intercostal muscles during inhalation?

  They contract, pulling the ribcage up and out.
• What is the effect of diaphragm contraction on lung volume?

  It increases the volume of the thoracic cavity.
• What is the concentration gradient's role in gas exchange?

  It drives the diffusion of gases from areas of high concentration to low concentration.
• Where does gas exchange take place?

  In the alveoli.
• What is one adaptation of the alveoli that aids in gas exchange?

  They have thin walls that are only one cell thick.
• How does the large number of alveoli benefit gas exchange?

  It provides a large surface area, increasing the rate of diffusion.
• Why is the lining of the alveoli moist?

  For dissolving gases.
• What happens to carbon dioxide in the alveoli?

  Carbon dioxide diffuses from the plasma in the blood into the alveoli.
• Why does carbon dioxide diffuse out of the alveoli?

  Because carbon dioxide concentration is higher in the blood than in the alveolus.
• What is the breathing rate formula?


  Breathing rate (bpm) = Number of breaths ÷ Time taken (minutes).
• If Mrs. Ihm takes 120 breaths in 7 minutes, what is her breathing rate?

  $17.2 \text{ bpm} =$$\frac{120}{7}$
• What determines how fast you need to breathe?

  The amount of oxygen required by your body cells.
• How does exercise affect breathing rate?

  You need more oxygen when you exercise, leading to a higher breathing rate.
• What happens to the breathing rate and volume of breathing during intense exercise?

  The breathing rate increases and the volume of breathing becomes greater.
• What is the process of oxygen moving from the alveolus into the red blood cell called?

  Diffusion.
• What does carbon dioxide do in the blood?

  Carbon dioxide diffuses from the plasma in the blood into the alveolus.
• Why does oxygen diffuse from the alveolus into the blood?

  Because oxygen concentration is higher in the alveolus than in the blood capillary.
• What is one difference between a healthy alveolus and one affected by emphysema?

  A healthy alveolus has a larger surface area.
• How does emphysema affect a person's ability to exercise?

  It causes less oxygen to enter the blood, leading to less respiration and therefore less energy released for exercise.
• What is the function of the alveoli in the lungs?

  Gas exchange occurs in the alveoli.
• What is one adaptation of the alveoli that increases the efficiency of gas exchange?

  They have a large surface area.
• What is the role of blood capillaries surrounding the alveoli?

  They maintain a steep concentration gradient of gases.
• Why is it important for the alveoli to be constantly ventilated?

  To maintain diffusion gradients.
• What is the main gas used in respiration?

  Oxygen.
• What is the purpose of the moist lining of the alveoli?

  For dissolving gases.