Lungs and gas exchange

• What is the primary function of the lungs?


  Gas exchange
• What is the name of the tube that carries air to the lungs?

  Trachea
• What are the tiny air sacs in the lungs called?

  Alveoli
• How do gases move between the alveolus and the blood?


  Gases diffuse between the alveolus and the blood
• What is the plural form of bronchus?


  Bronchi
• What type of blood enters the lungs from the body?


  Blood coming from the rest of the body has lots of CO₂
• What type of blood leaves the lungs to go to the rest of the body?


  Blood going to the rest of the body has lots of O₂
• What surrounds the alveoli in the lungs?


  • A capillary network
• How many alveoli are there in the lungs?


  There are millions of alveoli in the lungs
• What is the relationship between the alveoli and gas exchange?


  Alveoli facilitate gas exchange by allowing diffusion of gases
• If blood has high levels of CO₂, where is it likely coming from?


  It is likely coming from the rest of the body
• If blood is rich in O₂, what process has likely occurred?


  Gas exchange in the lungs
• What is the primary function of the lungs in gas exchange?


  To get oxygen from the air into the body
• Why do our cells need to perform cellular respiration?


  Because they need oxygen to produce energy
• What is the process of breathing in air called?

  Inhalation
• How does air travel through the respiratory system?


  Air passes through the mouth/nose and down the trachea
• What happens to air after it divides between the two bronchi?


  It further divides into bronchioles
• What are alveoli and what is their function?


  Alveoli are small sacs where gas exchange occurs
• What is the structure of an alveolus?


  Made of one layer of very thin cells
• Why is the thinness of alveolar walls important?


  It creates a short diffusion path for gases
• How does the large surface area of alveoli benefit gas exchange?


  It increases the rate at which CO₂ and oxygen can diffuse
• Why are the walls of alveoli moist?


  To allow gases to dissolve and increase the rate of diffusion
• What happens to blood in capillaries returning to the lungs?


  It has already given up most of its oxygen to tissues
• What is the concentration gradient of oxygen in the alveoli?


  It is higher in the alveoli than in the blood
• What occurs to oxygen once it diffuses into the bloodstream?


  It starts the cycle of oxygenation again
• What happens to the oxygen in the alveoli after it is used by the body?


  It is breathed out
• What type of blood enters the capillaries after gas exchange?


  Oxygenated blood
• What is the process of gas exchange in the lungs?


  • Air enters through mouth/nose and travels down the trachea
  • Divides into bronchi and further into bronchioles
  • Reaches alveoli where gas exchange occurs
  • Oxygen diffuses into blood, CO₂ diffuses into alveoli
  • Oxygenated blood returns to the body
• What is the primary function of the lungs?


  To get oxygen into the bloodstream and remove carbon dioxide
• How do the lungs facilitate gas exchange?


  By allowing oxygen to enter the blood and carbon dioxide to exit
• Where are the lungs located in the body?


  In the thorax
• What separates the thorax from the lower part of the body?

  The diaphragm
• What surrounds the lungs?

  Pleural membranes
• What is the structure of the lungs described as?


  Like big pink sponges
• What protects the lungs?

  The ribcage
• What is the pathway of air into the lungs?

  Through the trachea, which splits into bronchi
• What are the bronchi?


  Two tubes that lead to each lung
• What do the bronchi split into?


  Bronchioles
• Where does gas exchange take place in the lungs?


  In the alveoli
• What are alveoli?


  Small air sacs in the lungs