the lungs & gas exchange

• The lungs play a vital role in gas exchange, specifically to provide the body with oxygen
• Trace the pathway of air from inhalation to gas exchange in the lungs.

  1️⃣ Mouth or nose

  2️⃣ Trachea

  3️⃣ Bronchi

  4️⃣ Bronchioles

  5️⃣ Alveoli
• The alveoli are arranged like bunches of grapes
• What process do cells use oxygen for to produce energy?

  Cellular respiration
• What are the alveoli made up of?

  Single layer of cells
• The thin walls of the alveoli create a short diffusion pathway.
• Why do the alveoli have a large surface area?

  To increase diffusion
• The moist alveolar walls allow gases to dissolve
• The red blood cells in the capillaries surrounding the alveoli carry oxygenated blood to the body.
• Carbon dioxide is dissolved in blood plasma
• Carbon dioxide is carried by red blood cells in the blood.

  False
• Describe the continuous cycle of gas exchange in the lungs.

  1️⃣ Deoxygenated blood enters capillaries

  2️⃣ Oxygen diffuses from alveoli into blood

  3️⃣ Oxygenated blood leaves capillaries

  4️⃣ Deoxygenated blood re-enters
• What is the concentration gradient that allows oxygen to diffuse into the blood?

  High oxygen in alveoli
• Breathing rate is calculated in breaths per minute
• What happens to breathing rate during exercise?

  Increases
• If someone takes 30 breaths in 2 minutes, their breathing rate is15 breaths per minute.
• What does breathing rate measure?

  Breaths per minute